pgindent run for release 9.3

This is the first run of the Perl-based pgindent script.  Also update
pgindent instructions.

contrib/btree_gist/btree_bit.c

@@ -97,7 +97,6 @@ gbt_bit_xfrm(bytea *leaf)
 static GBT_VARKEY *
 gbt_bit_l2n(GBT_VARKEY *leaf)
 {
-
 	GBT_VARKEY *out = leaf;
 	GBT_VARKEY_R r = gbt_var_key_readable(leaf);
 	bytea	   *o;

contrib/btree_gist/btree_text.c

@@ -121,7 +121,6 @@ gbt_text_compress(PG_FUNCTION_ARGS)
 Datum
 gbt_bpchar_compress(PG_FUNCTION_ARGS)
 {
-
 	GISTENTRY  *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
 	GISTENTRY  *retval;
 

contrib/btree_gist/btree_ts.c

@@ -382,7 +382,6 @@ gbt_ts_union(PG_FUNCTION_ARGS)
 Datum
 gbt_ts_penalty(PG_FUNCTION_ARGS)
 {
-
 	tsKEY	   *origentry = (tsKEY *) DatumGetPointer(((GISTENTRY *) PG_GETARG_POINTER(0))->key);
 	tsKEY	   *newentry = (tsKEY *) DatumGetPointer(((GISTENTRY *) PG_GETARG_POINTER(1))->key);
 	float	   *result = (float *) PG_GETARG_POINTER(2);

contrib/btree_gist/btree_utils_num.c

@@ -137,7 +137,6 @@ gbt_num_union(GBT_NUMKEY *out, const GistEntryVector *entryvec, const gbtree_nin
 bool
 gbt_num_same(const GBT_NUMKEY *a, const GBT_NUMKEY *b, const gbtree_ninfo *tinfo)
 {
-
 	GBT_NUMKEY_R b1,
 				b2;
 
@@ -159,7 +158,6 @@ gbt_num_same(const GBT_NUMKEY *a, const GBT_NUMKEY *b, const gbtree_ninfo *tinfo
 void
 gbt_num_bin_union(Datum *u, GBT_NUMKEY *e, const gbtree_ninfo *tinfo)
 {
-
 	GBT_NUMKEY_R rd;
 
 	rd.lower = &e[0];

contrib/btree_gist/btree_utils_var.c

@@ -56,7 +56,6 @@ gbt_var_decompress(PG_FUNCTION_ARGS)
 GBT_VARKEY_R
 gbt_var_key_readable(const GBT_VARKEY *k)
 {
-
 	GBT_VARKEY_R r;
 
 	r.lower = (bytea *) &(((char *) k)[VARHDRSZ]);
@@ -270,7 +269,6 @@ gbt_var_bin_union(Datum *u, GBT_VARKEY *e, Oid collation,
 GISTENTRY *
 gbt_var_compress(GISTENTRY *entry, const gbtree_vinfo *tinfo)
 {
-
 	GISTENTRY  *retval;
 
 	if (entry->leafkey)
@@ -299,7 +297,6 @@ GBT_VARKEY *
 gbt_var_union(const GistEntryVector *entryvec, int32 *size, Oid collation,
 			  const gbtree_vinfo *tinfo)
 {
-
 	int			i = 0,
 				numranges = entryvec->n;
 	GBT_VARKEY *cur;

contrib/dblink/dblink.c

@@ -1984,9 +1984,9 @@ dblink_fdw_validator(PG_FUNCTION_ARGS)
 		if (!is_valid_dblink_option(options, def->defname, context))
 		{
 			/*
-			 * Unknown option, or invalid option for the context specified,
+			 * Unknown option, or invalid option for the context specified, so
-			 * so complain about it.  Provide a hint with list of valid
+			 * complain about it.  Provide a hint with list of valid options
-			 * options for the context.
+			 * for the context.
 			 */
 			StringInfoData buf;
 			const PQconninfoOption *opt;

contrib/pg_archivecleanup/pg_archivecleanup.c

@@ -299,8 +299,8 @@ main(int argc, char **argv)
 				dryrun = true;
 				break;
 			case 'x':
-				additional_ext = strdup(optarg);		/* Extension to remove from
+				additional_ext = strdup(optarg);		/* Extension to remove
-												 * xlogfile names */
+														 * from xlogfile names */
 				break;
 			default:
 				fprintf(stderr, "Try \"%s --help\" for more information.\n", progname);

contrib/pg_test_timing/pg_test_timing.c

@@ -110,8 +110,11 @@ test_timing(int32 duration)
 	uint64		total_time;
 	int64		time_elapsed = 0;
 	uint64		loop_count = 0;
-	uint64		prev, cur;
+	uint64		prev,
-	instr_time	start_time, end_time, temp;
+				cur;
+	instr_time	start_time,
+				end_time,
+				temp;
 
 	total_time = duration > 0 ? duration * 1000000 : 0;
 
@@ -120,7 +123,8 @@ test_timing(int32 duration)
 
 	while (time_elapsed < total_time)
 	{
-		int32		diff, bits = 0;
+		int32		diff,
+					bits = 0;
 
 		prev = cur;
 		INSTR_TIME_SET_CURRENT(temp);
@@ -163,7 +167,8 @@ test_timing(int32 duration)
 static void
 output(uint64 loop_count)
 {
-	int64		max_bit = 31, i;
+	int64		max_bit = 31,
+				i;
 
 	/* find highest bit value */
 	while (max_bit > 0 && histogram[max_bit] == 0)

contrib/pg_trgm/trgm_op.c

@@ -347,8 +347,8 @@ get_wildcard_part(const char *str, int lenstr,
 			else
 			{
 				/*
-				 * Back up endword to the escape character when stopping at
+				 * Back up endword to the escape character when stopping at an
-				 * an escaped char, so that subsequent get_wildcard_part will
+				 * escaped char, so that subsequent get_wildcard_part will
 				 * restart from the escape character.  We assume here that
 				 * escape chars are single-byte.
 				 */

contrib/pg_upgrade/check.c

@@ -46,11 +46,9 @@ fix_path_separator(char *path)
 			*c = '\\';
 
 	return result;
-
 #else
 
 	return path;
-
 #endif
 }
 
@@ -164,9 +162,9 @@ check_new_cluster(void)
 			   "Old and new cluster install users have different values for pg_authid.oid.\n");
 
 	/*
-	 *	We only allow the install user in the new cluster because other
+	 * We only allow the install user in the new cluster because other defined
-	 *	defined users might match users defined in the old cluster and
+	 * users might match users defined in the old cluster and generate an
-	 *	generate an error during pg_dump restore.
+	 * error during pg_dump restore.
 	 */
 	if (new_cluster.role_count != 1)
 		pg_log(PG_FATAL, "Only the install user can be defined in the new cluster.\n");
@@ -366,9 +364,9 @@ set_locale_and_encoding(ClusterInfo *cluster)
 		if (GET_MAJOR_VERSION(cluster->major_version) < 902)
 		{
 			/*
-			 *	Pre-9.2 did not canonicalize the supplied locale names
+			 * Pre-9.2 did not canonicalize the supplied locale names to match
-			 *	to match what the system returns, while 9.2+ does, so
+			 * what the system returns, while 9.2+ does, so convert pre-9.2 to
-			 *	convert pre-9.2 to match.
+			 * match.
 			 */
 			ctrl->lc_collate = get_canonical_locale_name(LC_COLLATE,
 								pg_strdup(PQgetvalue(res, 0, i_datcollate)));
@@ -598,8 +596,8 @@ create_script_for_old_cluster_deletion(char **deletion_script_file_name)
 
 	/*
 	 * Some users (oddly) create tablespaces inside the cluster data
-	 *	directory.  We can't create a proper old cluster delete script
+	 * directory.  We can't create a proper old cluster delete script in that
-	 *	in that case.
+	 * case.
 	 */
 	strlcpy(old_cluster_pgdata, old_cluster.pgdata, MAXPGPATH);
 	canonicalize_path(old_cluster_pgdata);

contrib/pg_upgrade/controldata.c

@@ -472,10 +472,10 @@ get_control_data(ClusterInfo *cluster, bool live_check)
 	pg_free(lc_messages);
 
 	/*
-	 * Before 9.3, pg_resetxlog reported the xlogid and segno of the first
+	 * Before 9.3, pg_resetxlog reported the xlogid and segno of the first log
-	 * log file after reset as separate lines. Starting with 9.3, it reports
+	 * file after reset as separate lines. Starting with 9.3, it reports the
-	 * the WAL file name. If the old cluster is older than 9.3, we construct
+	 * WAL file name. If the old cluster is older than 9.3, we construct the
-	 * the WAL file name from the xlogid and segno.
+	 * WAL file name from the xlogid and segno.
 	 */
 	if (GET_MAJOR_VERSION(cluster->major_version) <= 902)
 	{
@@ -621,7 +621,10 @@ check_control_data(ControlData *oldctrl,
 			   "options.\n");
 	}
 
-	/* We might eventually allow upgrades from checksum to no-checksum clusters. */
+	/*
+	 * We might eventually allow upgrades from checksum to no-checksum
+	 * clusters.
+	 */
 	if (oldctrl->data_checksum_version != newctrl->data_checksum_version)
 	{
 		pg_log(PG_FATAL,

contrib/pg_upgrade/exec.c

@@ -44,6 +44,7 @@ exec_prog(const char *log_file, const char *opt_log_file,
 {
 	int			result;
 	int			written;
+
 #define MAXCMDLEN (2 * MAXPGPATH)
 	char		cmd[MAXCMDLEN];
 	mode_t		old_umask = 0;
@@ -68,14 +69,14 @@ exec_prog(const char *log_file, const char *opt_log_file,
 #ifdef WIN32
 	{
 		/*
-		 * "pg_ctl -w stop" might have reported that the server has
+		 * "pg_ctl -w stop" might have reported that the server has stopped
-		 * stopped because the postmaster.pid file has been removed,
+		 * because the postmaster.pid file has been removed, but "pg_ctl -w
-		 * but "pg_ctl -w start" might still be in the process of
+		 * start" might still be in the process of closing and might still be
-		 * closing and might still be holding its stdout and -l log
+		 * holding its stdout and -l log file descriptors open.  Therefore,
-		 * file descriptors open.  Therefore, try to open the log 
+		 * try to open the log file a few more times.
-		 * file a few more times.
 		 */
 		int			iter;
+
 		for (iter = 0; iter < 4 && log == NULL; iter++)
 		{
 			sleep(1);
@@ -122,10 +123,11 @@ exec_prog(const char *log_file, const char *opt_log_file,
 	}
 
 #ifndef WIN32
+
 	/*
 	 * We can't do this on Windows because it will keep the "pg_ctl start"
-	 *	output filename open until the server stops, so we do the \n\n above
+	 * output filename open until the server stops, so we do the \n\n above on
-	 *	on that platform.  We use a unique filename for "pg_ctl start" that is
+	 * that platform.  We use a unique filename for "pg_ctl start" that is
 	 * never reused while the server is running, so it works fine.	We could
 	 * log these commands to a third file, but that just adds complexity.
 	 */
@@ -178,7 +180,6 @@ pid_lock_file_exists(const char *datadir)
 void
 verify_directories(void)
 {
-
 #ifndef WIN32
 	if (access(".", R_OK | W_OK | X_OK) != 0)
 #else

contrib/pg_upgrade/file.c

@@ -127,7 +127,6 @@ linkAndUpdateFile(pageCnvCtx *pageConverter,
 static int
 copy_file(const char *srcfile, const char *dstfile, bool force)
 {
-
 #define COPY_BUF_SIZE (50 * BLCKSZ)
 
 	int			src_fd;

contrib/pg_upgrade/info.c

@@ -60,10 +60,9 @@ gen_db_file_maps(DbInfo *old_db, DbInfo *new_db,
 		 * table names change during ALTER TABLE ALTER COLUMN SET TYPE. In >=
 		 * 9.0, TOAST relation names always use heap table oids, hence we
 		 * cannot check relation names when upgrading from pre-9.0. Clusters
-		 * upgraded to 9.0 will get matching TOAST names.
+		 * upgraded to 9.0 will get matching TOAST names. If index names don't
-		 * If index names don't match primary key constraint names, this will
+		 * match primary key constraint names, this will fail because pg_dump
-		 * fail because pg_dump dumps constraint names and pg_upgrade checks
+		 * dumps constraint names and pg_upgrade checks index names.
-		 * index names.
 		 */
 		if (strcmp(old_rel->nspname, new_rel->nspname) != 0 ||
 			((GET_MAJOR_VERSION(old_cluster.major_version) >= 900 ||
@@ -79,7 +78,10 @@ gen_db_file_maps(DbInfo *old_db, DbInfo *new_db,
 		num_maps++;
 	}
 
-	/* Do this check after the loop so hopefully we will produce a clearer error above */
+	/*
+	 * Do this check after the loop so hopefully we will produce a clearer
+	 * error above
+	 */
 	if (old_db->rel_arr.nrels != new_db->rel_arr.nrels)
 		pg_log(PG_FATAL, "old and new databases \"%s\" have a different number of relations\n",
 			   old_db->db_name);
@@ -285,8 +287,11 @@ get_rel_infos(ClusterInfo *cluster, DbInfo *dbinfo)
 			 "LEFT OUTER JOIN pg_catalog.pg_index i "
 			 "	   ON c.oid = i.indexrelid "
 			 "WHERE relkind IN ('r', 'm', 'i'%s) AND "
-			/* pg_dump only dumps valid indexes;  testing indisready is
+
-			 * necessary in 9.2, and harmless in earlier/later versions. */
+	/*
+	 * pg_dump only dumps valid indexes;  testing indisready is necessary in
+	 * 9.2, and harmless in earlier/later versions.
+	 */
 			 " i.indisvalid IS DISTINCT FROM false AND "
 			 " i.indisready IS DISTINCT FROM false AND "
 	/* exclude possible orphaned temp tables */

contrib/pg_upgrade/option.c

@@ -314,8 +314,8 @@ check_required_directory(char **dirpath, char **configpath,
 	}
 
 	/*
-	 * Trim off any trailing path separators because we construct paths
+	 * Trim off any trailing path separators because we construct paths by
-	 * by appending to this path.
+	 * appending to this path.
 	 */
 #ifndef WIN32
 	if ((*dirpath)[strlen(*dirpath) - 1] == '/')
@@ -398,10 +398,10 @@ void
 get_sock_dir(ClusterInfo *cluster, bool live_check)
 {
 #ifdef HAVE_UNIX_SOCKETS
+
 	/*
-	 *	sockdir and port were added to postmaster.pid in PG 9.1.
+	 * sockdir and port were added to postmaster.pid in PG 9.1. Pre-9.1 cannot
-	 *	Pre-9.1 cannot process pg_ctl -w for sockets in non-default
+	 * process pg_ctl -w for sockets in non-default locations.
-	 *	locations.
 	 */
 	if (GET_MAJOR_VERSION(cluster->major_version) >= 901)
 	{
@@ -415,11 +415,13 @@ get_sock_dir(ClusterInfo *cluster, bool live_check)
 		else
 		{
 			/*
-			 *	If we are doing a live check, we will use the old cluster's Unix
+			 * If we are doing a live check, we will use the old cluster's
-			 *	domain socket directory so we can connect to the live server.
+			 * Unix domain socket directory so we can connect to the live
+			 * server.
 			 */
 			unsigned short orig_port = cluster->port;
-			char		filename[MAXPGPATH], line[MAXPGPATH];
+			char		filename[MAXPGPATH],
+						line[MAXPGPATH];
 			FILE	   *fp;
 			int			lineno;
 
@@ -454,9 +456,12 @@ get_sock_dir(ClusterInfo *cluster, bool live_check)
 		}
 	}
 	else
-		/* Can't get sockdir and pg_ctl -w can't use a non-default, use default */
-		cluster->sockdir = NULL;
 
+		/*
+		 * Can't get sockdir and pg_ctl -w can't use a non-default, use
+		 * default
+		 */
+		cluster->sockdir = NULL;
 #else							/* !HAVE_UNIX_SOCKETS */
 	cluster->sockdir = NULL;
 #endif

contrib/pg_upgrade/page.c

@@ -59,9 +59,9 @@ setupPageConverter(void)
 	if (newPageVersion != oldPageVersion)
 	{
 		/*
-		 * The clusters use differing page layouts, see if we can find a plugin
+		 * The clusters use differing page layouts, see if we can find a
-		 * that knows how to convert from the old page layout to the new page
+		 * plugin that knows how to convert from the old page layout to the
-		 * layout.
+		 * new page layout.
 		 */
 
 		if ((converter = loadConverterPlugin(newPageVersion, oldPageVersion)) == NULL)
@@ -161,6 +161,4 @@ loadConverterPlugin(uint16 newPageVersion, uint16 oldPageVersion)
 	}
 }
 
-
-
 #endif

contrib/pg_upgrade/parallel.c

@@ -30,13 +30,15 @@ static int parallel_jobs;
  */
 HANDLE	   *thread_handles;
 
-typedef struct {
+typedef struct
+{
 	char		log_file[MAXPGPATH];
 	char		opt_log_file[MAXPGPATH];
 	char		cmd[MAX_STRING];
 } exec_thread_arg;
 
-typedef struct {
+typedef struct
+{
 	DbInfoArr  *old_db_arr;
 	DbInfoArr  *new_db_arr;
 	char		old_pgdata[MAXPGPATH];
@@ -52,7 +54,6 @@ void **cur_thread_args;
 
 DWORD		win32_exec_prog(exec_thread_arg *args);
 DWORD		win32_transfer_all_new_dbs(transfer_thread_arg *args);
-
 #endif
 
 /*
@@ -67,6 +68,7 @@ parallel_exec_prog(const char *log_file, const char *opt_log_file,
 {
 	va_list		args;
 	char		cmd[MAX_STRING];
+
 #ifndef WIN32
 	pid_t		child;
 #else
@@ -119,8 +121,8 @@ parallel_exec_prog(const char *log_file, const char *opt_log_file,
 
 			/*
 			 * For safety and performance, we keep the args allocated during
-			 *	the entire life of the process, and we don't free the args
+			 * the entire life of the process, and we don't free the args in a
-			 *	in a thread different from the one that allocated it.
+			 * thread different from the one that allocated it.
 			 */
 			for (i = 0; i < user_opts.jobs; i++)
 				exec_thread_args[i] = pg_malloc(sizeof(exec_thread_arg));
@@ -167,7 +169,8 @@ win32_exec_prog(exec_thread_arg *args)
  *	This has the same API as transfer_all_new_dbs, except it does parallel execution
  *	by transfering multiple tablespaces in parallel
  */
-void parallel_transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
+void
+parallel_transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
 							  char *old_pgdata, char *new_pgdata,
 							  char *old_tablespace)
 {
@@ -224,8 +227,8 @@ void parallel_transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
 
 			/*
 			 * For safety and performance, we keep the args allocated during
-			 *	the entire life of the process, and we don't free the args
+			 * the entire life of the process, and we don't free the args in a
-			 *	in a thread different from the one that allocated it.
+			 * thread different from the one that allocated it.
 			 */
 			for (i = 0; i < user_opts.jobs; i++)
 				transfer_thread_args[i] = pg_malloc(sizeof(transfer_thread_arg));
@@ -293,7 +296,6 @@ reap_child(bool wait_for_child)
 
 	if (WEXITSTATUS(work_status) != 0)
 		pg_log(PG_FATAL, "child worker exited abnormally: %s\n", strerror(errno));
-
 #else
 	/* wait for one to finish */
 	thread_num = WaitForMultipleObjects(parallel_jobs, thread_handles,
@@ -321,10 +323,10 @@ reap_child(bool wait_for_child)
 		thread_handles[thread_num] = thread_handles[parallel_jobs - 1];
 
 		/*
-		 *	We must swap the arg struct pointers because the thread we
+		 * We must swap the arg struct pointers because the thread we just
-		 *	just moved is active, and we must make sure it is not
+		 * moved is active, and we must make sure it is not reused by the next
-		 *	reused by the next created thread.  Instead, the new thread
+		 * created thread.	Instead, the new thread will use the arg struct of
-		 *	will use the arg struct of the thread that just died.
+		 * the thread that just died.
 		 */
 		tmp_args = cur_thread_args[thread_num];
 		cur_thread_args[thread_num] = cur_thread_args[parallel_jobs - 1];

contrib/pg_upgrade/pg_upgrade.c

@@ -193,13 +193,12 @@ setup(char *argv0, bool *live_check)
 	if (pid_lock_file_exists(old_cluster.pgdata))
 	{
 		/*
-		 *	If we have a postmaster.pid file, try to start the server.  If
+		 * If we have a postmaster.pid file, try to start the server.  If it
-		 *	it starts, the pid file was stale, so stop the server.  If it
+		 * starts, the pid file was stale, so stop the server.	If it doesn't
-		 *	doesn't start, assume the server is running.  If the pid file
+		 * start, assume the server is running.  If the pid file is left over
-		 *	is left over from a server crash, this also allows any committed
+		 * from a server crash, this also allows any committed transactions
-		 *	transactions stored in the WAL to be replayed so they are not
+		 * stored in the WAL to be replayed so they are not lost, because WAL
-		 *	lost, because WAL files are not transfered from old to new
+		 * files are not transfered from old to new servers.
-		 *	servers.
 		 */
 		if (start_postmaster(&old_cluster, false))
 			stop_postmaster(false);
@@ -313,8 +312,8 @@ create_new_objects(void)
 
 	/*
 	 * Technically, we only need to install these support functions in new
-	 *	databases that also exist in the old cluster, but for completeness
+	 * databases that also exist in the old cluster, but for completeness we
-	 *	we process all new databases.
+	 * process all new databases.
 	 */
 	for (dbnum = 0; dbnum < new_cluster.dbarr.ndbs; dbnum++)
 	{
@@ -330,7 +329,8 @@ create_new_objects(void)
 
 	for (dbnum = 0; dbnum < old_cluster.dbarr.ndbs; dbnum++)
 	{
-		char sql_file_name[MAXPGPATH], log_file_name[MAXPGPATH];
+		char		sql_file_name[MAXPGPATH],
+					log_file_name[MAXPGPATH];
 		DbInfo	   *old_db = &old_cluster.dbarr.dbs[dbnum];
 
 		pg_log(PG_STATUS, "%s", old_db->db_name);
@@ -418,6 +418,7 @@ copy_clog_xlog_xid(void)
 		copy_subdir_files("pg_multixact/offsets");
 		copy_subdir_files("pg_multixact/members");
 		prep_status("Setting next multixact ID and offset for new cluster");
+
 		/*
 		 * we preserve all files and contents, so we must preserve both "next"
 		 * counters here and the oldest multi present on system.
@@ -434,6 +435,7 @@ copy_clog_xlog_xid(void)
 	else if (new_cluster.controldata.cat_ver >= MULTIXACT_FORMATCHANGE_CAT_VER)
 	{
 		prep_status("Setting oldest multixact ID on new cluster");
+
 		/*
 		 * We don't preserve files in this case, but it's important that the
 		 * oldest multi is set to the latest value used by the old system, so
@@ -549,7 +551,6 @@ set_frozenxids(void)
 static void
 cleanup(void)
 {
-
 	fclose(log_opts.internal);
 
 	/* Remove dump and log files? */
@@ -567,7 +568,8 @@ cleanup(void)
 		if (old_cluster.dbarr.dbs)
 			for (dbnum = 0; dbnum < old_cluster.dbarr.ndbs; dbnum++)
 			{
-				char sql_file_name[MAXPGPATH], log_file_name[MAXPGPATH];
+				char		sql_file_name[MAXPGPATH],
+							log_file_name[MAXPGPATH];
 				DbInfo	   *old_db = &old_cluster.dbarr.dbs[dbnum];
 
 				snprintf(sql_file_name, sizeof(sql_file_name), DB_DUMP_FILE_MASK, old_db->db_oid);

contrib/pg_upgrade/pg_upgrade.h

@@ -477,11 +477,11 @@ void old_8_3_invalidate_bpchar_pattern_ops_indexes(ClusterInfo *cluster,
 char	   *old_8_3_create_sequence_script(ClusterInfo *cluster);
 
 /* parallel.c */
-void		parallel_exec_prog(const char *log_file, const char *opt_log_file,
+void
+parallel_exec_prog(const char *log_file, const char *opt_log_file,
 				   const char *fmt,...)
 __attribute__((format(PG_PRINTF_ATTRIBUTE, 3, 4)));
 void parallel_transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
 							  char *old_pgdata, char *new_pgdata,
 							  char *old_tablespace);
 bool		reap_child(bool wait_for_child);
-

contrib/pg_upgrade/relfilenode.c

@@ -35,11 +35,11 @@ transfer_all_new_tablespaces(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
 	  user_opts.transfer_mode == TRANSFER_MODE_LINK ? "Linking" : "Copying");
 
 	/*
-	 *	Transfering files by tablespace is tricky because a single database
+	 * Transfering files by tablespace is tricky because a single database can
-	 *	can use multiple tablespaces.  For non-parallel mode, we just pass a
+	 * use multiple tablespaces.  For non-parallel mode, we just pass a NULL
-	 *	NULL tablespace path, which matches all tablespaces.  In parallel mode,
+	 * tablespace path, which matches all tablespaces.	In parallel mode, we
-	 *	we pass the default tablespace and all user-created tablespaces
+	 * pass the default tablespace and all user-created tablespaces and let
-	 *	and let those operations happen in parallel.
+	 * those operations happen in parallel.
 	 */
 	if (user_opts.jobs <= 1)
 		parallel_transfer_all_new_dbs(old_db_arr, new_db_arr, old_pgdata,
@@ -219,11 +219,9 @@ transfer_relfile(pageCnvCtx *pageConverter, FileNameMap *map,
 	char		extent_suffix[65];
 
 	/*
-	 * Now copy/link any related segments as well. Remember, PG breaks
+	 * Now copy/link any related segments as well. Remember, PG breaks large
-	 * large files into 1GB segments, the first segment has no extension,
+	 * files into 1GB segments, the first segment has no extension, subsequent
-	 * subsequent segments are named relfilenode.1, relfilenode.2,
+	 * segments are named relfilenode.1, relfilenode.2, relfilenode.3. copied.
-	 * relfilenode.3.
-	 * copied.
 	 */
 	for (segno = 0;; segno++)
 	{
@@ -286,4 +284,3 @@ transfer_relfile(pageCnvCtx *pageConverter, FileNameMap *map,
 
 	return;
 }
-

contrib/pg_xlogdump/pg_xlogdump.c

@@ -89,6 +89,7 @@ static bool
 verify_directory(const char *directory)
 {
 	DIR		   *dir = opendir(directory);
+
 	if (dir == NULL)
 		return false;
 	closedir(dir);
@@ -672,9 +673,9 @@ main(int argc, char **argv)
 					(uint32) private.startptr);
 
 	/*
-	 * Display a message that we're skipping data if `from` wasn't a pointer to
+	 * Display a message that we're skipping data if `from` wasn't a pointer
-	 * the start of a record and also wasn't a pointer to the beginning of a
+	 * to the start of a record and also wasn't a pointer to the beginning of
-	 * segment (e.g. we were used in file mode).
+	 * a segment (e.g. we were used in file mode).
 	 */
 	if (first_record != private.startptr && (private.startptr % XLogSegSize) != 0)
 		printf("first record is after %X/%X, at %X/%X, skipping over %u bytes\n",

contrib/pg_xlogdump/rmgrdesc.c

@@ -33,4 +33,3 @@
 const RmgrDescData RmgrDescTable[RM_MAX_ID + 1] = {
 #include "access/rmgrlist.h"
 };
-

contrib/pgbench/pgbench.c

@@ -162,7 +162,8 @@ char	   *index_tablespace = NULL;
 
 bool		use_log;			/* log transaction latencies to a file */
 bool		use_quiet;			/* quiet logging onto stderr */
-int			agg_interval;		/* log aggregates instead of individual transactions */
+int			agg_interval;		/* log aggregates instead of individual
+								 * transactions */
 bool		is_connect;			/* establish connection for each transaction */
 bool		is_latencies;		/* report per-command latencies */
 int			main_pid;			/* main process id used in log filename */
@@ -265,7 +266,8 @@ typedef struct
 	int			cnt;			/* number of transactions */
 	double		min_duration;	/* min/max durations */
 	double		max_duration;
-	double	sum;				/* sum(duration), sum(duration^2) - for estimates */
+	double		sum;			/* sum(duration), sum(duration^2) - for
+								 * estimates */
 	double		sum2;
 
 } AggVals;
@@ -874,7 +876,8 @@ clientDone(CState *st, bool ok)
 }
 
 static
-void agg_vals_init(AggVals * aggs, instr_time start)
+void
+agg_vals_init(AggVals *aggs, instr_time start)
 {
 	/* basic counters */
 	aggs->cnt = 0;				/* number of transactions */
@@ -964,8 +967,10 @@ top:
 				/* should we aggregate the results or not? */
 				if (agg_interval > 0)
 				{
-					/* are we still in the same interval? if yes, accumulate the
+					/*
-					* values (print them otherwise) */
+					 * are we still in the same interval? if yes, accumulate
+					 * the values (print them otherwise)
+					 */
 					if (agg->start_time + agg_interval >= INSTR_TIME_GET_DOUBLE(now))
 					{
 						agg->cnt += 1;
@@ -981,12 +986,18 @@ top:
 					}
 					else
 					{
-						/* Loop until we reach the interval of the current transaction (and
+						/*
-						 * print all the empty intervals in between). */
+						 * Loop until we reach the interval of the current
+						 * transaction (and print all the empty intervals in
+						 * between).
+						 */
 						while (agg->start_time + agg_interval < INSTR_TIME_GET_DOUBLE(now))
 						{
-							/* This is a non-Windows branch (thanks to the ifdef in usage), so
+							/*
-							 * we don't need to handle this in a special way (see below). */
+							 * This is a non-Windows branch (thanks to the
+							 * ifdef in usage), so we don't need to handle
+							 * this in a special way (see below).
+							 */
 							fprintf(logfile, "%ld %d %.0f %.0f %.0f %.0f\n",
 							  agg->start_time, agg->cnt, agg->sum, agg->sum2,
 									agg->min_duration, agg->max_duration);
@@ -1002,7 +1013,10 @@ top:
 							agg->sum2 = 0;
 						}
 
-						/* and now update the reset values (include the current) */
+						/*
+						 * and now update the reset values (include the
+						 * current)
+						 */
 						agg->cnt = 1;
 						agg->min_duration = usec;
 						agg->max_duration = usec;
@@ -1014,12 +1028,20 @@ top:
 				{
 					/* no, print raw transactions */
 #ifndef WIN32
-					/* This is more than we really ought to know about instr_time */
+
+					/*
+					 * This is more than we really ought to know about
+					 * instr_time
+					 */
 					fprintf(logfile, "%d %d %.0f %d %ld %ld\n",
 							st->id, st->cnt, usec, st->use_file,
 							(long) now.tv_sec, (long) now.tv_usec);
 #else
-					/* On Windows, instr_time doesn't provide a timestamp anyway */
+
+					/*
+					 * On Windows, instr_time doesn't provide a timestamp
+					 * anyway
+					 */
 					fprintf(logfile, "%d %d %.0f %d 0 0\n",
 							st->id, st->cnt, usec, st->use_file);
 #endif
@@ -1234,11 +1256,11 @@ top:
 			}
 
 			/*
-			 * getrand() needs to be able to subtract max from min and add
+			 * getrand() needs to be able to subtract max from min and add one
-			 * one to the result without overflowing.  Since we know max > min,
+			 * to the result without overflowing.  Since we know max > min, we
-			 * we can detect overflow just by checking for a negative result.
+			 * can detect overflow just by checking for a negative result. But
-			 * But we must check both that the subtraction doesn't overflow,
+			 * we must check both that the subtraction doesn't overflow, and
-			 * and that adding one to the result doesn't overflow either.
+			 * that adding one to the result doesn't overflow either.
 			 */
 			if (max - min < 0 || (max - min) + 1 < 0)
 			{
@@ -1418,7 +1440,6 @@ disconnect_all(CState *state, int length)
 static void
 init(bool is_no_vacuum)
 {
-
 /* The scale factor at/beyond which 32bit integers are incapable of storing
  * 64bit values.
  *
@@ -1488,8 +1509,10 @@ init(bool is_no_vacuum)
 	int64		k;
 
 	/* used to track elapsed time and estimate of the remaining time */
-	instr_time	start, diff;
+	instr_time	start,
-	double		elapsed_sec, remaining_sec;
+				diff;
+	double		elapsed_sec,
+				remaining_sec;
 	int			log_interval = 1;
 
 	if ((con = doConnect()) == NULL)
@@ -1573,8 +1596,10 @@ init(bool is_no_vacuum)
 			exit(1);
 		}
 
-		/* If we want to stick with the original logging, print a message each
+		/*
-		 * 100k inserted rows. */
+		 * If we want to stick with the original logging, print a message each
+		 * 100k inserted rows.
+		 */
 		if ((!use_quiet) && (j % 100000 == 0))
 		{
 			INSTR_TIME_SET_CURRENT(diff);
@@ -1598,7 +1623,8 @@ init(bool is_no_vacuum)
 			remaining_sec = (scale * naccounts - j) * elapsed_sec / j;
 
 			/* have we reached the next interval (or end)? */
-			if ((j == scale * naccounts) || (elapsed_sec >= log_interval * LOG_STEP_SECONDS)) {
+			if ((j == scale * naccounts) || (elapsed_sec >= log_interval * LOG_STEP_SECONDS))
+			{
 
 				fprintf(stderr, INT64_FORMAT " of " INT64_FORMAT " tuples (%d%%) done (elapsed %.2f s, remaining %.2f s).\n",
 						j, (int64) naccounts * scale,
@@ -2393,17 +2419,20 @@ main(int argc, char **argv)
 		exit(1);
 	}
 
-	if (agg_interval > 0 && (! use_log)) {
+	if (agg_interval > 0 && (!use_log))
+	{
 		fprintf(stderr, "log aggregation is allowed only when actually logging transactions\n");
 		exit(1);
 	}
 
-	if ((duration > 0) && (agg_interval > duration)) {
+	if ((duration > 0) && (agg_interval > duration))
+	{
 		fprintf(stderr, "number of seconds for aggregation (%d) must not be higher that test duration (%d)\n", agg_interval, duration);
 		exit(1);
 	}
 
-	if ((duration > 0) && (agg_interval > 0) && (duration % agg_interval != 0)) {
+	if ((duration > 0) && (agg_interval > 0) && (duration % agg_interval != 0))
+	{
 		fprintf(stderr, "duration (%d) must be a multiple of aggregation interval (%d)\n", duration, agg_interval);
 		exit(1);
 	}

contrib/pgcrypto/imath.h

@@ -117,14 +117,11 @@ mp_result	mp_int_mul_value(mp_int a, int value, mp_int c);
 mp_result	mp_int_mul_pow2(mp_int a, int p2, mp_int c);
 mp_result	mp_int_sqr(mp_int a, mp_int c);		/* c = a * a */
 
-mp_result
+mp_result mp_int_div(mp_int a, mp_int b,	/* q = a / b */
-mp_int_div(mp_int a, mp_int b,	/* q = a / b */
 		   mp_int q, mp_int r); /* r = a % b */
-mp_result
+mp_result mp_int_div_value(mp_int a, int value,	/* q = a / value */
-mp_int_div_value(mp_int a, int value,	/* q = a / value */
 				 mp_int q, int *r);		/* r = a % value */
-mp_result
+mp_result mp_int_div_pow2(mp_int a, int p2,		/* q = a / 2^p2  */
-mp_int_div_pow2(mp_int a, int p2,		/* q = a / 2^p2  */
 				mp_int q, mp_int r);	/* r = q % 2^p2  */
 mp_result	mp_int_mod(mp_int a, mp_int m, mp_int c);	/* c = a % m */
 
@@ -143,17 +140,13 @@ int			mp_int_divisible_value(mp_int a, int v);
 /* Returns k >= 0 such that z = 2^k, if one exists; otherwise < 0 */
 int			mp_int_is_pow2(mp_int z);
 
-mp_result
+mp_result mp_int_exptmod(mp_int a, mp_int b, mp_int m,
-mp_int_exptmod(mp_int a, mp_int b, mp_int m,
 			   mp_int c);		/* c = a^b (mod m) */
-mp_result
+mp_result mp_int_exptmod_evalue(mp_int a, int value,
-mp_int_exptmod_evalue(mp_int a, int value,
 					  mp_int m, mp_int c);		/* c = a^v (mod m) */
-mp_result
+mp_result mp_int_exptmod_bvalue(int value, mp_int b,
-mp_int_exptmod_bvalue(int value, mp_int b,
 					  mp_int m, mp_int c);		/* c = v^b (mod m) */
-mp_result
+mp_result mp_int_exptmod_known(mp_int a, mp_int b,
-mp_int_exptmod_known(mp_int a, mp_int b,
 					 mp_int m, mp_int mu,
 					 mp_int c); /* c = a^b (mod m) */
 mp_result	mp_int_redux_const(mp_int m, mp_int c);
@@ -162,8 +155,7 @@ mp_result	mp_int_invmod(mp_int a, mp_int m, mp_int c);		/* c = 1/a (mod m) */
 
 mp_result	mp_int_gcd(mp_int a, mp_int b, mp_int c);	/* c = gcd(a, b)   */
 
-mp_result
+mp_result mp_int_egcd(mp_int a, mp_int b, mp_int c,		/* c = gcd(a, b)   */
-mp_int_egcd(mp_int a, mp_int b, mp_int c,		/* c = gcd(a, b)   */
 			mp_int x, mp_int y);	/* c = ax + by	   */
 
 mp_result	mp_int_sqrt(mp_int a, mp_int c);	/* c = floor(sqrt(q)) */

contrib/pgcrypto/pgp.h

@@ -265,8 +265,7 @@ int			pgp_s2k_read(PullFilter *src, PGP_S2K *s2k);
 int			pgp_s2k_process(PGP_S2K *s2k, int cipher, const uint8 *key, int klen);
 
 typedef struct PGP_CFB PGP_CFB;
-int
+int pgp_cfb_create(PGP_CFB **ctx_p, int algo,
-pgp_cfb_create(PGP_CFB **ctx_p, int algo,
 			   const uint8 *key, int key_len, int recync, uint8 *iv);
 void		pgp_cfb_free(PGP_CFB *ctx);
 int			pgp_cfb_encrypt(PGP_CFB *ctx, const uint8 *data, int len, uint8 *dst);

contrib/pgrowlocks/pgrowlocks.c

@@ -280,8 +280,8 @@ pgrowlocks(PG_FUNCTION_ARGS)
 			result = HeapTupleGetDatum(tuple);
 
 			/*
-			 * no need to pfree what we allocated; it's on a short-lived memory
+			 * no need to pfree what we allocated; it's on a short-lived
-			 * context anyway
+			 * memory context anyway
 			 */
 
 			SRF_RETURN_NEXT(funcctx, result);

contrib/sepgsql/hooks.c

@@ -211,9 +211,9 @@ sepgsql_object_access(ObjectAccessType access,
 							/*
 							 * A case when we don't want to apply permission
 							 * check is that relation is internally altered
-							 * without user's intention. E.g, no need to
+							 * without user's intention. E.g, no need to check
-							 * check on toast table/index to be renamed at
+							 * on toast table/index to be renamed at end of
-							 * end of the table rewrites.
+							 * the table rewrites.
 							 */
 							if (is_internal)
 								break;
@@ -241,8 +241,8 @@ sepgsql_object_access(ObjectAccessType access,
 				ObjectAccessNamespaceSearch *ns_arg = arg;
 
 				/*
-				 * If stacked extension already decided not to allow users
+				 * If stacked extension already decided not to allow users to
-				 * to search this schema, we just stick with that decision.
+				 * search this schema, we just stick with that decision.
 				 */
 				if (!ns_arg->result)
 					break;

contrib/sepgsql/label.c

@@ -351,9 +351,8 @@ sepgsql_fmgr_hook(FmgrHookEventType event,
 				 *
 				 * Also, db_procedure:entrypoint permission should be checked
 				 * whether this procedure can perform as an entrypoint of the
-				 * trusted procedure, or not.
+				 * trusted procedure, or not. Note that db_procedure:execute
-				 * Note that db_procedure:execute permission shall be checked
+				 * permission shall be checked individually.
-				 * individually.
 				 */
 				if (stack->new_label)
 				{

contrib/sepgsql/schema.c

@@ -81,6 +81,7 @@ sepgsql_schema_post_create(Oid namespaceId)
 									  tcontext,
 									  SEPG_CLASS_DB_SCHEMA,
 									  nsp_name);
+
 	/*
 	 * check db_schema:{create}
 	 */

contrib/worker_spi/worker_spi.c

@@ -237,11 +237,11 @@ worker_spi_main(void *main_arg)
 		 * start time is always up to date.
 		 *
 		 * The SPI_connect() call lets us run queries through the SPI manager,
-		 * and the PushActiveSnapshot() call creates an "active" snapshot which
+		 * and the PushActiveSnapshot() call creates an "active" snapshot
-		 * is necessary for queries to have MVCC data to work on.
+		 * which is necessary for queries to have MVCC data to work on.
 		 *
-		 * The pgstat_report_activity() call makes our activity visible through
+		 * The pgstat_report_activity() call makes our activity visible
-		 * the pgstat views.
+		 * through the pgstat views.
 		 */
 		SetCurrentStatementStartTimestamp();
 		StartTransactionCommand();

src/backend/access/gin/ginbtree.c

@@ -173,7 +173,6 @@ void
 ginFindParents(GinBtree btree, GinBtreeStack *stack,
 			   BlockNumber rootBlkno)
 {
-
 	Page		page;
 	Buffer		buffer;
 	BlockNumber blkno,

src/backend/access/gist/gistget.c

@@ -364,8 +364,9 @@ gistScanPage(IndexScanDesc scan, GISTSearchItem *pageItem, double *myDistances,
 				item->blkno = ItemPointerGetBlockNumber(&it->t_tid);
 
 				/*
-				 * LSN of current page is lsn of parent page for child. We only
+				 * LSN of current page is lsn of parent page for child. We
-				 * have a shared lock, so we need to get the LSN atomically.
+				 * only have a shared lock, so we need to get the LSN
+				 * atomically.
 				 */
 				item->data.parentlsn = BufferGetLSNAtomic(buffer);
 			}

src/backend/access/gist/gistutil.c

@@ -810,8 +810,8 @@ gistGetFakeLSN(Relation rel)
 	if (rel->rd_rel->relpersistence == RELPERSISTENCE_TEMP)
 	{
 		/*
-		 * Temporary relations are only accessible in our session, so a
+		 * Temporary relations are only accessible in our session, so a simple
-		 * simple backend-local counter will do.
+		 * backend-local counter will do.
 		 */
 		return counter++;
 	}

src/backend/access/heap/heapam.c

@@ -123,6 +123,7 @@ static const struct
 	MultiXactStatus lockstatus;
 	MultiXactStatus updstatus;
 }
+
 			tupleLockExtraInfo[MaxLockTupleMode + 1] =
 {
 	{							/* LockTupleKeyShare */
@@ -146,6 +147,7 @@ tupleLockExtraInfo[MaxLockTupleMode + 1] =
 		MultiXactStatusUpdate
 	}
 };
+
 /* Get the LOCKMODE for a given MultiXactStatus */
 #define LOCKMODE_from_mxstatus(status) \
 			(tupleLockExtraInfo[TUPLOCK_from_mxstatus((status))].hwlock)
@@ -365,10 +367,10 @@ heapgetpage(HeapScanDesc scan, BlockNumber page)
 	 * page. That's how index-only scans work fine in hot standby. A crucial
 	 * difference between index-only scans and heap scans is that the
 	 * index-only scan completely relies on the visibility map where as heap
-	 * scan looks at the page-level PD_ALL_VISIBLE flag. We are not sure if the
+	 * scan looks at the page-level PD_ALL_VISIBLE flag. We are not sure if
-	 * page-level flag can be trusted in the same way, because it might get
+	 * the page-level flag can be trusted in the same way, because it might
-	 * propagated somehow without being explicitly WAL-logged, e.g. via a full
+	 * get propagated somehow without being explicitly WAL-logged, e.g. via a
-	 * page write. Until we can prove that beyond doubt, let's check each
+	 * full page write. Until we can prove that beyond doubt, let's check each
 	 * tuple for visibility the hard way.
 	 */
 	all_visible = PageIsAllVisible(dp) && !snapshot->takenDuringRecovery;
@@ -2730,13 +2732,12 @@ l1:
 	}
 
 	/*
-	 * If this is the first possibly-multixact-able operation in the
+	 * If this is the first possibly-multixact-able operation in the current
-	 * current transaction, set my per-backend OldestMemberMXactId setting.
+	 * transaction, set my per-backend OldestMemberMXactId setting. We can be
-	 * We can be certain that the transaction will never become a member of
+	 * certain that the transaction will never become a member of any older
-	 * any older MultiXactIds than that.  (We have to do this even if we
+	 * MultiXactIds than that.	(We have to do this even if we end up just
-	 * end up just using our own TransactionId below, since some other
+	 * using our own TransactionId below, since some other backend could
-	 * backend could incorporate our XID into a MultiXact immediately
+	 * incorporate our XID into a MultiXact immediately afterwards.)
-	 * afterwards.)
 	 */
 	MultiXactIdSetOldestMember();
 
@@ -3006,13 +3007,13 @@ heap_update(Relation relation, ItemPointer otid, HeapTuple newtup,
 
 	/*
 	 * If we're not updating any "key" column, we can grab a weaker lock type.
-	 * This allows for more concurrency when we are running simultaneously with
+	 * This allows for more concurrency when we are running simultaneously
-	 * foreign key checks.
+	 * with foreign key checks.
 	 *
-	 * Note that if a column gets detoasted while executing the update, but the
+	 * Note that if a column gets detoasted while executing the update, but
-	 * value ends up being the same, this test will fail and we will use the
+	 * the value ends up being the same, this test will fail and we will use
-	 * stronger lock.  This is acceptable; the important case to optimize is
+	 * the stronger lock.  This is acceptable; the important case to optimize
-	 * updates that don't manipulate key columns, not those that
+	 * is updates that don't manipulate key columns, not those that
 	 * serendipitiously arrive at the same key values.
 	 */
 	HeapSatisfiesHOTandKeyUpdate(relation, hot_attrs, key_attrs,
@@ -3026,12 +3027,12 @@ heap_update(Relation relation, ItemPointer otid, HeapTuple newtup,
 
 		/*
 		 * If this is the first possibly-multixact-able operation in the
-		 * current transaction, set my per-backend OldestMemberMXactId setting.
+		 * current transaction, set my per-backend OldestMemberMXactId
-		 * We can be certain that the transaction will never become a member of
+		 * setting. We can be certain that the transaction will never become a
-		 * any older MultiXactIds than that.  (We have to do this even if we
+		 * member of any older MultiXactIds than that.	(We have to do this
-		 * end up just using our own TransactionId below, since some other
+		 * even if we end up just using our own TransactionId below, since
-		 * backend could incorporate our XID into a MultiXact immediately
+		 * some other backend could incorporate our XID into a MultiXact
-		 * afterwards.)
+		 * immediately afterwards.)
 		 */
 		MultiXactIdSetOldestMember();
 	}
@@ -3073,13 +3074,14 @@ l2:
 		/*
 		 * XXX note that we don't consider the "no wait" case here.  This
 		 * isn't a problem currently because no caller uses that case, but it
-		 * should be fixed if such a caller is introduced.  It wasn't a problem
+		 * should be fixed if such a caller is introduced.	It wasn't a
-		 * previously because this code would always wait, but now that some
+		 * problem previously because this code would always wait, but now
-		 * tuple locks do not conflict with one of the lock modes we use, it is
+		 * that some tuple locks do not conflict with one of the lock modes we
-		 * possible that this case is interesting to handle specially.
+		 * use, it is possible that this case is interesting to handle
+		 * specially.
 		 *
-		 * This may cause failures with third-party code that calls heap_update
+		 * This may cause failures with third-party code that calls
-		 * directly.
+		 * heap_update directly.
 		 */
 
 		/* must copy state data before unlocking buffer */
@@ -3109,10 +3111,10 @@ l2:
 		 * gone (or even not sleep at all in some cases); we need to preserve
 		 * it as locker, unless it is gone completely.
 		 *
-		 * If it's not a multi, we need to check for sleeping conditions before
+		 * If it's not a multi, we need to check for sleeping conditions
-		 * actually going to sleep.  If the update doesn't conflict with the
+		 * before actually going to sleep.	If the update doesn't conflict
-		 * locks, we just continue without sleeping (but making sure it is
+		 * with the locks, we just continue without sleeping (but making sure
-		 * preserved).
+		 * it is preserved).
 		 */
 		if (infomask & HEAP_XMAX_IS_MULTI)
 		{
@@ -3138,15 +3140,15 @@ l2:
 			 * Note that the multixact may not be done by now.	It could have
 			 * surviving members; our own xact or other subxacts of this
 			 * backend, and also any other concurrent transaction that locked
-			 * the tuple with KeyShare if we only got TupleLockUpdate.  If this
+			 * the tuple with KeyShare if we only got TupleLockUpdate.	If
-			 * is the case, we have to be careful to mark the updated tuple
+			 * this is the case, we have to be careful to mark the updated
-			 * with the surviving members in Xmax.
+			 * tuple with the surviving members in Xmax.
 			 *
-			 * Note that there could have been another update in the MultiXact.
+			 * Note that there could have been another update in the
-			 * In that case, we need to check whether it committed or aborted.
+			 * MultiXact. In that case, we need to check whether it committed
-			 * If it aborted we are safe to update it again; otherwise there is
+			 * or aborted. If it aborted we are safe to update it again;
-			 * an update conflict, and we have to return HeapTupleUpdated
+			 * otherwise there is an update conflict, and we have to return
-			 * below.
+			 * HeapTupleUpdated below.
 			 *
 			 * In the LockTupleExclusive case, we still need to preserve the
 			 * surviving members: those would include the tuple locks we had
@@ -3167,17 +3169,17 @@ l2:
 		else
 		{
 			/*
-			 * If it's just a key-share locker, and we're not changing the
+			 * If it's just a key-share locker, and we're not changing the key
-			 * key columns, we don't need to wait for it to end; but we
+			 * columns, we don't need to wait for it to end; but we need to
-			 * need to preserve it as locker.
+			 * preserve it as locker.
 			 */
 			if (HEAP_XMAX_IS_KEYSHR_LOCKED(infomask) && key_intact)
 			{
 				LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
 
 				/*
-				 * recheck the locker; if someone else changed the tuple while we
+				 * recheck the locker; if someone else changed the tuple while
-				 * weren't looking, start over.
+				 * we weren't looking, start over.
 				 */
 				if ((oldtup.t_data->t_infomask & HEAP_XMAX_IS_MULTI) ||
 				!TransactionIdEquals(HeapTupleHeaderGetRawXmax(oldtup.t_data),
@@ -3194,9 +3196,9 @@ l2:
 				LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
 
 				/*
-				 * xwait is done, but if xwait had just locked the tuple then some
+				 * xwait is done, but if xwait had just locked the tuple then
-				 * other xact could update this tuple before we get to this point.
+				 * some other xact could update this tuple before we get to
-				 * Check for xmax change, and start over if so.
+				 * this point. Check for xmax change, and start over if so.
 				 */
 				if ((oldtup.t_data->t_infomask & HEAP_XMAX_IS_MULTI) ||
 				!TransactionIdEquals(HeapTupleHeaderGetRawXmax(oldtup.t_data),
@@ -3247,8 +3249,8 @@ l2:
 	 * visible while we were busy locking the buffer, or during some
 	 * subsequent window during which we had it unlocked, we'll have to unlock
 	 * and re-lock, to avoid holding the buffer lock across an I/O.  That's a
-	 * bit unfortunate, especially since we'll now have to recheck whether
+	 * bit unfortunate, especially since we'll now have to recheck whether the
-	 * the tuple has been locked or updated under us, but hopefully it won't
+	 * tuple has been locked or updated under us, but hopefully it won't
 	 * happen very often.
 	 */
 	if (vmbuffer == InvalidBuffer && PageIsAllVisible(page))
@@ -3656,9 +3658,9 @@ heap_tuple_attr_equals(TupleDesc tupdesc, int attrnum,
 
 	/*
 	 * Extract the corresponding values.  XXX this is pretty inefficient if
-	 * there are many indexed columns.	Should HeapSatisfiesHOTandKeyUpdate do a
+	 * there are many indexed columns.	Should HeapSatisfiesHOTandKeyUpdate do
-	 * single heap_deform_tuple call on each tuple, instead?  But that doesn't
+	 * a single heap_deform_tuple call on each tuple, instead?	But that
-	 * work for system columns ...
+	 * doesn't work for system columns ...
 	 */
 	value1 = heap_getattr(tup1, attrnum, tupdesc, &isnull1);
 	value2 = heap_getattr(tup2, attrnum, tupdesc, &isnull2);
@@ -3944,11 +3946,11 @@ l3:
 		LockBuffer(*buffer, BUFFER_LOCK_UNLOCK);
 
 		/*
-		 * If any subtransaction of the current top transaction already holds a
+		 * If any subtransaction of the current top transaction already holds
-		 * lock as strong or stronger than what we're requesting, we
+		 * a lock as strong or stronger than what we're requesting, we
 		 * effectively hold the desired lock already.  We *must* succeed
-		 * without trying to take the tuple lock, else we will deadlock against
+		 * without trying to take the tuple lock, else we will deadlock
-		 * anyone wanting to acquire a stronger lock.
+		 * against anyone wanting to acquire a stronger lock.
 		 */
 		if (infomask & HEAP_XMAX_IS_MULTI)
 		{
@@ -3957,9 +3959,9 @@ l3:
 			MultiXactMember *members;
 
 			/*
-			 * We don't need to allow old multixacts here; if that had been the
+			 * We don't need to allow old multixacts here; if that had been
-			 * case, HeapTupleSatisfiesUpdate would have returned MayBeUpdated
+			 * the case, HeapTupleSatisfiesUpdate would have returned
-			 * and we wouldn't be here.
+			 * MayBeUpdated and we wouldn't be here.
 			 */
 			nmembers = GetMultiXactIdMembers(xwait, &members, false);
 
@@ -4023,20 +4025,20 @@ l3:
 			 * continue if the key hasn't been modified.
 			 *
 			 * However, if there are updates, we need to walk the update chain
-			 * to mark future versions of the row as locked, too.  That way, if
+			 * to mark future versions of the row as locked, too.  That way,
-			 * somebody deletes that future version, we're protected against
+			 * if somebody deletes that future version, we're protected
-			 * the key going away.  This locking of future versions could block
+			 * against the key going away.	This locking of future versions
-			 * momentarily, if a concurrent transaction is deleting a key; or
+			 * could block momentarily, if a concurrent transaction is
-			 * it could return a value to the effect that the transaction
+			 * deleting a key; or it could return a value to the effect that
-			 * deleting the key has already committed.  So we do this before
+			 * the transaction deleting the key has already committed.	So we
-			 * re-locking the buffer; otherwise this would be prone to
+			 * do this before re-locking the buffer; otherwise this would be
-			 * deadlocks.
+			 * prone to deadlocks.
 			 *
 			 * Note that the TID we're locking was grabbed before we unlocked
-			 * the buffer.  For it to change while we're not looking, the other
+			 * the buffer.	For it to change while we're not looking, the
-			 * properties we're testing for below after re-locking the buffer
+			 * other properties we're testing for below after re-locking the
-			 * would also change, in which case we would restart this loop
+			 * buffer would also change, in which case we would restart this
-			 * above.
+			 * loop above.
 			 */
 			if (!(infomask2 & HEAP_KEYS_UPDATED))
 			{
@@ -4045,8 +4047,8 @@ l3:
 				updated = !HEAP_XMAX_IS_LOCKED_ONLY(infomask);
 
 				/*
-				 * If there are updates, follow the update chain; bail out
+				 * If there are updates, follow the update chain; bail out if
-				 * if that cannot be done.
+				 * that cannot be done.
 				 */
 				if (follow_updates && updated)
 				{
@@ -4069,8 +4071,9 @@ l3:
 				/*
 				 * Make sure it's still an appropriate lock, else start over.
 				 * Also, if it wasn't updated before we released the lock, but
-				 * is updated now, we start over too; the reason is that we now
+				 * is updated now, we start over too; the reason is that we
-				 * need to follow the update chain to lock the new versions.
+				 * now need to follow the update chain to lock the new
+				 * versions.
 				 */
 				if (!HeapTupleHeaderIsOnlyLocked(tuple->t_data) &&
 					((tuple->t_data->t_infomask2 & HEAP_KEYS_UPDATED) ||
@@ -4114,8 +4117,8 @@ l3:
 		{
 			/*
 			 * If we're requesting NoKeyExclusive, we might also be able to
-			 * avoid sleeping; just ensure that there's no other lock type than
+			 * avoid sleeping; just ensure that there's no other lock type
-			 * KeyShare.  Note that this is a bit more involved than just
+			 * than KeyShare.  Note that this is a bit more involved than just
 			 * checking hint bits -- we need to expand the multixact to figure
 			 * out lock modes for each one (unless there was only one such
 			 * locker).
@@ -4126,8 +4129,8 @@ l3:
 				MultiXactMember *members;
 
 				/*
-				 * We don't need to allow old multixacts here; if that had been
+				 * We don't need to allow old multixacts here; if that had
-				 * the case, HeapTupleSatisfiesUpdate would have returned
+				 * been the case, HeapTupleSatisfiesUpdate would have returned
 				 * MayBeUpdated and we wouldn't be here.
 				 */
 				nmembers = GetMultiXactIdMembers(xwait, &members, false);
@@ -4135,8 +4138,8 @@ l3:
 				if (nmembers <= 0)
 				{
 					/*
-					 * No need to keep the previous xmax here. This is unlikely
+					 * No need to keep the previous xmax here. This is
-					 * to happen.
+					 * unlikely to happen.
 					 */
 					require_sleep = false;
 				}
@@ -4355,8 +4358,8 @@ failed:
 	 * for cases where it is a plain TransactionId.
 	 *
 	 * Note in particular that this covers the case where we already hold
-	 * exclusive lock on the tuple and the caller only wants key share or share
+	 * exclusive lock on the tuple and the caller only wants key share or
-	 * lock. It would certainly not do to give up the exclusive lock.
+	 * share lock. It would certainly not do to give up the exclusive lock.
 	 */
 	if (!(old_infomask & (HEAP_XMAX_INVALID |
 						  HEAP_XMAX_COMMITTED |
@@ -4379,13 +4382,12 @@ failed:
 	}
 
 	/*
-	 * If this is the first possibly-multixact-able operation in the
+	 * If this is the first possibly-multixact-able operation in the current
-	 * current transaction, set my per-backend OldestMemberMXactId setting.
+	 * transaction, set my per-backend OldestMemberMXactId setting. We can be
-	 * We can be certain that the transaction will never become a member of
+	 * certain that the transaction will never become a member of any older
-	 * any older MultiXactIds than that.  (We have to do this even if we
+	 * MultiXactIds than that.	(We have to do this even if we end up just
-	 * end up just using our own TransactionId below, since some other
+	 * using our own TransactionId below, since some other backend could
-	 * backend could incorporate our XID into a MultiXact immediately
+	 * incorporate our XID into a MultiXact immediately afterwards.)
-	 * afterwards.)
 	 */
 	MultiXactIdSetOldestMember();
 
@@ -4422,8 +4424,8 @@ failed:
 	 * Make sure there is no forward chain link in t_ctid.	Note that in the
 	 * cases where the tuple has been updated, we must not overwrite t_ctid,
 	 * because it was set by the updater.  Moreover, if the tuple has been
-	 * updated, we need to follow the update chain to lock the new versions
+	 * updated, we need to follow the update chain to lock the new versions of
-	 * of the tuple as well.
+	 * the tuple as well.
 	 */
 	if (HEAP_XMAX_IS_LOCKED_ONLY(new_infomask))
 		tuple->t_data->t_ctid = *tid;
@@ -4565,8 +4567,8 @@ l5:
 		MultiXactStatus new_status;
 
 		/*
-		 * Currently we don't allow XMAX_COMMITTED to be set for multis,
+		 * Currently we don't allow XMAX_COMMITTED to be set for multis, so
-		 * so cross-check.
+		 * cross-check.
 		 */
 		Assert(!(old_infomask & HEAP_XMAX_COMMITTED));
 
@@ -4587,10 +4589,11 @@ l5:
 
 		/*
 		 * If the XMAX is already a MultiXactId, then we need to expand it to
-		 * include add_to_xmax; but if all the members were lockers and are all
+		 * include add_to_xmax; but if all the members were lockers and are
-		 * gone, we can do away with the IS_MULTI bit and just set add_to_xmax
+		 * all gone, we can do away with the IS_MULTI bit and just set
-		 * as the only locker/updater.  If all lockers are gone and we have an
+		 * add_to_xmax as the only locker/updater.	If all lockers are gone
-		 * updater that aborted, we can also do without a multi.
+		 * and we have an updater that aborted, we can also do without a
+		 * multi.
 		 *
 		 * The cost of doing GetMultiXactIdMembers would be paid by
 		 * MultiXactIdExpand if we weren't to do this, so this check is not
@@ -4633,6 +4636,7 @@ l5:
 			status = MultiXactStatusNoKeyUpdate;
 
 		new_status = get_mxact_status_for_lock(mode, is_update);
+
 		/*
 		 * since it's not running, it's obviously impossible for the old
 		 * updater to be identical to the current one, so we need not check
@@ -4737,6 +4741,7 @@ l5:
 			status = MultiXactStatusNoKeyUpdate;
 
 		new_status = get_mxact_status_for_lock(mode, is_update);
+
 		/*
 		 * since it's not running, it's obviously impossible for the old
 		 * updater to be identical to the current one, so we need not check
@@ -4802,11 +4807,12 @@ l4:
 		xmax = HeapTupleHeaderGetRawXmax(mytup.t_data);
 
 		/*
-		 * If this tuple is updated and the key has been modified (or deleted),
+		 * If this tuple is updated and the key has been modified (or
-		 * what we do depends on the status of the updating transaction: if
+		 * deleted), what we do depends on the status of the updating
-		 * it's live, we sleep until it finishes; if it has committed, we have
+		 * transaction: if it's live, we sleep until it finishes; if it has
-		 * to fail (i.e. return HeapTupleUpdated); if it aborted, we ignore it.
+		 * committed, we have to fail (i.e. return HeapTupleUpdated); if it
-		 * For updates that didn't touch the key, we can just plough ahead.
+		 * aborted, we ignore it. For updates that didn't touch the key, we
+		 * can just plough ahead.
 		 */
 		if (!(old_infomask & HEAP_XMAX_INVALID) &&
 			(mytup.t_data->t_infomask2 & HEAP_KEYS_UPDATED))
@@ -4932,12 +4938,12 @@ heap_lock_updated_tuple(Relation rel, HeapTuple tuple, ItemPointer ctid,
 	{
 		/*
 		 * If this is the first possibly-multixact-able operation in the
-		 * current transaction, set my per-backend OldestMemberMXactId setting.
+		 * current transaction, set my per-backend OldestMemberMXactId
-		 * We can be certain that the transaction will never become a member of
+		 * setting. We can be certain that the transaction will never become a
-		 * any older MultiXactIds than that.  (We have to do this even if we
+		 * member of any older MultiXactIds than that.	(We have to do this
-		 * end up just using our own TransactionId below, since some other
+		 * even if we end up just using our own TransactionId below, since
-		 * backend could incorporate our XID into a MultiXact immediately
+		 * some other backend could incorporate our XID into a MultiXact
-		 * afterwards.)
+		 * immediately afterwards.)
 		 */
 		MultiXactIdSetOldestMember();
 
@@ -5117,9 +5123,9 @@ heap_freeze_tuple(HeapTupleHeader tuple, TransactionId cutoff_xid,
 		HeapTupleHeaderSetXmax(tuple, InvalidTransactionId);
 
 		/*
-		 * The tuple might be marked either XMAX_INVALID or XMAX_COMMITTED
+		 * The tuple might be marked either XMAX_INVALID or XMAX_COMMITTED +
-		 * + LOCKED.  Normalize to INVALID just to be sure no one gets
+		 * LOCKED.	Normalize to INVALID just to be sure no one gets confused.
-		 * confused.  Also get rid of the HEAP_KEYS_UPDATED bit.
+		 * Also get rid of the HEAP_KEYS_UPDATED bit.
 		 */
 		tuple->t_infomask &= ~HEAP_XMAX_BITS;
 		tuple->t_infomask |= HEAP_XMAX_INVALID;
@@ -5257,8 +5263,8 @@ MultiXactIdGetUpdateXid(TransactionId xmax, uint16 t_infomask)
 	Assert(t_infomask & HEAP_XMAX_IS_MULTI);
 
 	/*
-	 * Since we know the LOCK_ONLY bit is not set, this cannot be a
+	 * Since we know the LOCK_ONLY bit is not set, this cannot be a multi from
-	 * multi from pre-pg_upgrade.
+	 * pre-pg_upgrade.
 	 */
 	nmembers = GetMultiXactIdMembers(xmax, &members, false);
 
@@ -5284,6 +5290,7 @@ MultiXactIdGetUpdateXid(TransactionId xmax, uint16 t_infomask)
 				   members[i].status == MultiXactStatusUpdate);
 			update_xact = members[i].xid;
 #ifndef USE_ASSERT_CHECKING
+
 			/*
 			 * in an assert-enabled build, walk the whole array to ensure
 			 * there's no other updater.

src/backend/access/nbtree/nbtpage.c

@@ -532,8 +532,8 @@ _bt_log_reuse_page(Relation rel, BlockNumber blkno, TransactionId latestRemovedX
 	START_CRIT_SECTION();
 
 	/*
-	 * We don't do MarkBufferDirty here because we're about to initialise
+	 * We don't do MarkBufferDirty here because we're about to initialise the
-	 * the page, and nobody else can see it yet.
+	 * page, and nobody else can see it yet.
 	 */
 
 	/* XLOG stuff */
@@ -552,8 +552,8 @@ _bt_log_reuse_page(Relation rel, BlockNumber blkno, TransactionId latestRemovedX
 		XLogInsert(RM_BTREE_ID, XLOG_BTREE_REUSE_PAGE, rdata);
 
 		/*
-		 * We don't do PageSetLSN here because we're about to initialise
+		 * We don't do PageSetLSN here because we're about to initialise the
-		 * the page, so no need.
+		 * page, so no need.
 		 */
 	}
 

src/backend/access/nbtree/nbtxlog.c

@@ -608,8 +608,8 @@ btree_xlog_delete_get_latestRemovedXid(xl_btree_delete *xlrec)
 	 * In what follows, we have to examine the previous state of the index
 	 * page, as well as the heap page(s) it points to.	This is only valid if
 	 * WAL replay has reached a consistent database state; which means that
-	 * the preceding check is not just an optimization, but is *necessary*.
+	 * the preceding check is not just an optimization, but is *necessary*. We
-	 * We won't have let in any user sessions before we reach consistency.
+	 * won't have let in any user sessions before we reach consistency.
 	 */
 	if (!reachedConsistency)
 		elog(PANIC, "btree_xlog_delete_get_latestRemovedXid: cannot operate with inconsistent data");
@@ -701,10 +701,10 @@ btree_xlog_delete_get_latestRemovedXid(xl_btree_delete *xlrec)
 
 	/*
 	 * XXX If all heap tuples were LP_DEAD then we will be returning
-	 * InvalidTransactionId here, causing conflict for all HS
+	 * InvalidTransactionId here, causing conflict for all HS transactions.
-	 * transactions. That should happen very rarely (reasoning please?). Also
+	 * That should happen very rarely (reasoning please?). Also note that
-	 * note that caller can't tell the difference between this case and the
+	 * caller can't tell the difference between this case and the fast path
-	 * fast path exit above. May need to change that in future.
+	 * exit above. May need to change that in future.
 	 */
 	return latestRemovedXid;
 }

src/backend/access/rmgrdesc/xlogdesc.c

@@ -85,6 +85,7 @@ xlog_desc(StringInfo buf, uint8 xl_info, char *rec)
 	else if (info == XLOG_HINT)
 	{
 		BkpBlock   *bkp = (BkpBlock *) rec;
+
 		appendStringInfo(buf, "page hint: %s block %u",
 						 relpathperm(bkp->node, bkp->fork),
 						 bkp->block);

src/backend/access/transam/multixact.c

@@ -177,8 +177,8 @@ typedef struct MultiXactStateData
 	MultiXactId lastTruncationPoint;
 
 	/*
-	 * oldest multixact that is still on disk.  Anything older than this should
+	 * oldest multixact that is still on disk.	Anything older than this
-	 * not be consulted.
+	 * should not be consulted.
 	 */
 	MultiXactId oldestMultiXactId;
 	Oid			oldestMultiXactDB;
@@ -387,9 +387,9 @@ MultiXactIdExpand(MultiXactId multi, TransactionId xid, MultiXactStatus status)
 				multi, xid, mxstatus_to_string(status));
 
 	/*
-	 * Note: we don't allow for old multis here.  The reason is that the
+	 * Note: we don't allow for old multis here.  The reason is that the only
-	 * only caller of this function does a check that the multixact is
+	 * caller of this function does a check that the multixact is no longer
-	 * no longer running.
+	 * running.
 	 */
 	nmembers = GetMultiXactIdMembers(multi, &members, false);
 
@@ -430,14 +430,14 @@ MultiXactIdExpand(MultiXactId multi, TransactionId xid, MultiXactStatus status)
 	}
 
 	/*
-	 * Determine which of the members of the MultiXactId are still of interest.
+	 * Determine which of the members of the MultiXactId are still of
-	 * This is any running transaction, and also any transaction that grabbed
+	 * interest. This is any running transaction, and also any transaction
-	 * something stronger than just a lock and was committed.  (An update that
+	 * that grabbed something stronger than just a lock and was committed.
-	 * aborted is of no interest here.)
+	 * (An update that aborted is of no interest here.)
 	 *
-	 * (Removing dead members is just an optimization, but a useful one.
+	 * (Removing dead members is just an optimization, but a useful one. Note
-	 * Note we have the same race condition here as above: j could be 0 at the
+	 * we have the same race condition here as above: j could be 0 at the end
-	 * end of the loop.)
+	 * of the loop.)
 	 */
 	newMembers = (MultiXactMember *)
 		palloc(sizeof(MultiXactMember) * (nmembers + 1));
@@ -722,9 +722,9 @@ CreateMultiXactId(int nmembers, MultiXactMember *members)
 
 	/*
 	 * XXX Note: there's a lot of padding space in MultiXactMember.  We could
-	 * find a more compact representation of this Xlog record -- perhaps all the
+	 * find a more compact representation of this Xlog record -- perhaps all
-	 * status flags in one XLogRecData, then all the xids in another one?  Not
+	 * the status flags in one XLogRecData, then all the xids in another one?
-	 * clear that it's worth the trouble though.
+	 * Not clear that it's worth the trouble though.
 	 */
 	rdata[0].data = (char *) (&xlrec);
 	rdata[0].len = SizeOfMultiXactCreate;
@@ -995,10 +995,10 @@ GetNewMultiXactId(int nmembers, MultiXactOffset *offset)
 	 *
 	 * We don't care about MultiXactId wraparound here; it will be handled by
 	 * the next iteration.	But note that nextMXact may be InvalidMultiXactId
-	 * or the first value on a segment-beginning page after this routine exits,
+	 * or the first value on a segment-beginning page after this routine
-	 * so anyone else looking at the variable must be prepared to deal with
+	 * exits, so anyone else looking at the variable must be prepared to deal
-	 * either case.  Similarly, nextOffset may be zero, but we won't use that
+	 * with either case.  Similarly, nextOffset may be zero, but we won't use
-	 * as the actual start offset of the next multixact.
+	 * that as the actual start offset of the next multixact.
 	 */
 	(MultiXactState->nextMXact)++;
 
@@ -1066,9 +1066,9 @@ GetMultiXactIdMembers(MultiXactId multi, MultiXactMember **members,
 	 *
 	 * An ID older than MultiXactState->oldestMultiXactId cannot possibly be
 	 * useful; it should have already been frozen by vacuum.  We've truncated
-	 * the on-disk structures anyway.  Returning the wrong values could lead to
+	 * the on-disk structures anyway.  Returning the wrong values could lead
-	 * an incorrect visibility result.  However, to support pg_upgrade we need
+	 * to an incorrect visibility result.  However, to support pg_upgrade we
-	 * to allow an empty set to be returned regardless, if the caller is
+	 * need to allow an empty set to be returned regardless, if the caller is
 	 * willing to accept it; the caller is expected to check that it's an
 	 * allowed condition (such as ensuring that the infomask bits set on the
 	 * tuple are consistent with the pg_upgrade scenario).	If the caller is
@@ -1076,8 +1076,8 @@ GetMultiXactIdMembers(MultiXactId multi, MultiXactMember **members,
 	 * raise an error.
 	 *
 	 * Conversely, an ID >= nextMXact shouldn't ever be seen here; if it is
-	 * seen, it implies undetected ID wraparound has occurred.	This raises
+	 * seen, it implies undetected ID wraparound has occurred.	This raises a
-	 * a hard error.
+	 * hard error.
 	 *
 	 * Shared lock is enough here since we aren't modifying any global state.
 	 * Acquire it just long enough to grab the current counter values.	We may
@@ -1911,11 +1911,11 @@ SetMultiXactIdLimit(MultiXactId oldest_datminmxid, Oid oldest_datoid)
 		multiStopLimit -= FirstMultiXactId;
 
 	/*
-	 * We'll start complaining loudly when we get within 10M multis of the stop
+	 * We'll start complaining loudly when we get within 10M multis of the
-	 * point.	This is kind of arbitrary, but if you let your gas gauge get
+	 * stop point.	 This is kind of arbitrary, but if you let your gas gauge
-	 * down to 1% of full, would you be looking for the next gas station?  We
+	 * get down to 1% of full, would you be looking for the next gas station?
-	 * need to be fairly liberal about this number because there are lots of
+	 * We need to be fairly liberal about this number because there are lots
-	 * scenarios where most transactions are done by automatic clients that
+	 * of scenarios where most transactions are done by automatic clients that
 	 * won't pay attention to warnings. (No, we're not gonna make this
 	 * configurable.  If you know enough to configure it, you know enough to
 	 * not get in this kind of trouble in the first place.)
@@ -1925,8 +1925,8 @@ SetMultiXactIdLimit(MultiXactId oldest_datminmxid, Oid oldest_datoid)
 		multiWarnLimit -= FirstMultiXactId;
 
 	/*
-	 * We'll start trying to force autovacuums when oldest_datminmxid gets
+	 * We'll start trying to force autovacuums when oldest_datminmxid gets to
-	 * to be more than 200 million transactions old.
+	 * be more than 200 million transactions old.
 	 */
 	multiVacLimit = oldest_datminmxid + 200000000;
 	if (multiVacLimit < FirstMultiXactId)
@@ -2207,9 +2207,9 @@ TruncateMultiXact(MultiXactId oldestMXact)
 	/*
 	 * Note we can't just plow ahead with the truncation; it's possible that
 	 * there are no segments to truncate, which is a problem because we are
-	 * going to attempt to read the offsets page to determine where to truncate
+	 * going to attempt to read the offsets page to determine where to
-	 * the members SLRU.  So we first scan the directory to determine the
+	 * truncate the members SLRU.  So we first scan the directory to determine
-	 * earliest offsets page number that we can read without error.
+	 * the earliest offsets page number that we can read without error.
 	 */
 	trunc.earliestExistingPage = -1;
 	SlruScanDirectory(MultiXactOffsetCtl, SlruScanDirCbFindEarliest, &trunc);
@@ -2220,9 +2220,9 @@ TruncateMultiXact(MultiXactId oldestMXact)
 		return;
 
 	/*
-	 * First, compute the safe truncation point for MultiXactMember.
+	 * First, compute the safe truncation point for MultiXactMember. This is
-	 * This is the starting offset of the multixact we were passed
+	 * the starting offset of the multixact we were passed as MultiXactOffset
-	 * as MultiXactOffset cutoff.
+	 * cutoff.
 	 */
 	{
 		int			pageno;

src/backend/access/transam/timeline.c

@@ -179,8 +179,8 @@ readTimeLineHistory(TimeLineID targetTLI)
 			errhint("Timeline IDs must be less than child timeline's ID.")));
 
 	/*
-	 * Create one more entry for the "tip" of the timeline, which has no
+	 * Create one more entry for the "tip" of the timeline, which has no entry
-	 * entry in the history file.
+	 * in the history file.
 	 */
 	entry = (TimeLineHistoryEntry *) palloc(sizeof(TimeLineHistoryEntry));
 	entry->tli = targetTLI;
@@ -553,6 +553,7 @@ tliOfPointInHistory(XLogRecPtr ptr, List *history)
 	foreach(cell, history)
 	{
 		TimeLineHistoryEntry *tle = (TimeLineHistoryEntry *) lfirst(cell);
+
 		if ((XLogRecPtrIsInvalid(tle->begin) || tle->begin <= ptr) &&
 			(XLogRecPtrIsInvalid(tle->end) || ptr < tle->end))
 		{

src/backend/access/transam/xact.c

@@ -1024,8 +1024,8 @@ RecordTransactionCommit(void)
 		 *
 		 * It's safe to change the delayChkpt flag of our own backend without
 		 * holding the ProcArrayLock, since we're the only one modifying it.
-		 * This makes checkpoint's determination of which xacts are delayChkpt a
+		 * This makes checkpoint's determination of which xacts are delayChkpt
-		 * bit fuzzy, but it doesn't matter.
+		 * a bit fuzzy, but it doesn't matter.
 		 */
 		START_CRIT_SECTION();
 		MyPgXact->delayChkpt = true;
@@ -4683,12 +4683,11 @@ xact_redo_commit_internal(TransactionId xid, XLogRecPtr lsn,
 	 * from the template database, and then commit the transaction. If we
 	 * crash after all the files have been copied but before the commit, you
 	 * have files in the data directory without an entry in pg_database. To
-	 * minimize the window
+	 * minimize the window for that, we use ForceSyncCommit() to rush the
-	 * for that, we use ForceSyncCommit() to rush the commit record to disk as
+	 * commit record to disk as quick as possible. We have the same window
-	 * quick as possible. We have the same window during recovery, and forcing
+	 * during recovery, and forcing an XLogFlush() (which updates
-	 * an XLogFlush() (which updates minRecoveryPoint during recovery) helps
+	 * minRecoveryPoint during recovery) helps to reduce that problem window,
-	 * to reduce that problem window, for any user that requested
+	 * for any user that requested ForceSyncCommit().
-	 * ForceSyncCommit().
 	 */
 	if (XactCompletionForceSyncCommit(xinfo))
 		XLogFlush(lsn);

src/backend/access/transam/xlog.c

@@ -403,7 +403,8 @@ typedef struct XLogCtlData
 	uint32		ckptXidEpoch;	/* nextXID & epoch of latest checkpoint */
 	TransactionId ckptXid;
 	XLogRecPtr	asyncXactLSN;	/* LSN of newest async commit/abort */
-	XLogSegNo	lastRemovedSegNo; /* latest removed/recycled XLOG segment */
+	XLogSegNo	lastRemovedSegNo;		/* latest removed/recycled XLOG
+										 * segment */
 
 	/* Fake LSN counter, for unlogged relations. Protected by ulsn_lck */
 	XLogRecPtr	unloggedLSN;
@@ -1251,10 +1252,10 @@ XLogCheckBuffer(XLogRecData *rdata, bool holdsExclusiveLock,
 	page = BufferGetPage(rdata->buffer);
 
 	/*
-	 * We assume page LSN is first data on *every* page that can be passed
+	 * We assume page LSN is first data on *every* page that can be passed to
-	 * to XLogInsert, whether it has the standard page layout or not. We
+	 * XLogInsert, whether it has the standard page layout or not. We don't
-	 * don't need to take the buffer header lock for PageGetLSN if we hold
+	 * need to take the buffer header lock for PageGetLSN if we hold an
-	 * an exclusive lock on the page and/or the relation.
+	 * exclusive lock on the page and/or the relation.
 	 */
 	if (holdsExclusiveLock)
 		*lsn = PageGetLSN(page);
@@ -1979,8 +1980,8 @@ XLogFlush(XLogRecPtr record)
 		/*
 		 * Sleep before flush! By adding a delay here, we may give further
 		 * backends the opportunity to join the backlog of group commit
-		 * followers; this can significantly improve transaction throughput, at
+		 * followers; this can significantly improve transaction throughput,
-		 * the risk of increasing transaction latency.
+		 * at the risk of increasing transaction latency.
 		 *
 		 * We do not sleep if enableFsync is not turned on, nor if there are
 		 * fewer than CommitSiblings other backends with active transactions.
@@ -3215,8 +3216,8 @@ RestoreBackupBlockContents(XLogRecPtr lsn, BkpBlock bkpb, char *blk,
 	}
 
 	/*
-	 * The checksum value on this page is currently invalid. We don't
+	 * The checksum value on this page is currently invalid. We don't need to
-	 * need to reset it here since it will be set before being written.
+	 * reset it here since it will be set before being written.
 	 */
 
 	PageSetLSN(page, lsn);
@@ -3272,16 +3273,17 @@ ReadRecord(XLogReaderState *xlogreader, XLogRecPtr RecPtr, int emode,
 			}
 
 			/*
-			 * We only end up here without a message when XLogPageRead() failed
+			 * We only end up here without a message when XLogPageRead()
-			 * - in that case we already logged something.
+			 * failed - in that case we already logged something. In
-			 * In StandbyMode that only happens if we have been triggered, so
+			 * StandbyMode that only happens if we have been triggered, so we
-			 * we shouldn't loop anymore in that case.
+			 * shouldn't loop anymore in that case.
 			 */
 			if (errormsg)
 				ereport(emode_for_corrupt_record(emode,
 												 RecPtr ? RecPtr : EndRecPtr),
 				(errmsg_internal("%s", errormsg) /* already translated */ ));
 		}
+
 		/*
 		 * Check page TLI is one of the expected values.
 		 */
@@ -3314,10 +3316,10 @@ ReadRecord(XLogReaderState *xlogreader, XLogRecPtr RecPtr, int emode,
 			lastSourceFailed = true;
 
 			/*
-			 * If archive recovery was requested, but we were still doing crash
+			 * If archive recovery was requested, but we were still doing
-			 * recovery, switch to archive recovery and retry using the offline
+			 * crash recovery, switch to archive recovery and retry using the
-			 * archive. We have now replayed all the valid WAL in pg_xlog, so
+			 * offline archive. We have now replayed all the valid WAL in
-			 * we are presumably now consistent.
+			 * pg_xlog, so we are presumably now consistent.
 			 *
 			 * We require that there's at least some valid WAL present in
 			 * pg_xlog, however (!fetch_ckpt). We could recover using the WAL
@@ -3401,8 +3403,8 @@ rescanLatestTimeLine(void)
 	newExpectedTLEs = readTimeLineHistory(newtarget);
 
 	/*
-	 * If the current timeline is not part of the history of the new
+	 * If the current timeline is not part of the history of the new timeline,
-	 * timeline, we cannot proceed to it.
+	 * we cannot proceed to it.
 	 */
 	found = false;
 	foreach(cell, newExpectedTLEs)
@@ -4998,8 +5000,8 @@ StartupXLOG(void)
 						  &backupFromStandby))
 	{
 		/*
-		 * Archive recovery was requested, and thanks to the backup label file,
+		 * Archive recovery was requested, and thanks to the backup label
-		 * we know how far we need to replay to reach consistency. Enter
+		 * file, we know how far we need to replay to reach consistency. Enter
 		 * archive recovery directly.
 		 */
 		InArchiveRecovery = true;
@@ -5049,8 +5051,8 @@ StartupXLOG(void)
 		/*
 		 * It's possible that archive recovery was requested, but we don't
 		 * know how far we need to replay the WAL before we reach consistency.
-		 * This can happen for example if a base backup is taken from a running
+		 * This can happen for example if a base backup is taken from a
-		 * server using an atomic filesystem snapshot, without calling
+		 * running server using an atomic filesystem snapshot, without calling
 		 * pg_start/stop_backup. Or if you just kill a running master server
 		 * and put it into archive recovery by creating a recovery.conf file.
 		 *
@@ -5058,8 +5060,8 @@ StartupXLOG(void)
 		 * replaying all the WAL present in pg_xlog, and only enter archive
 		 * recovery after that.
 		 *
-		 * But usually we already know how far we need to replay the WAL (up to
+		 * But usually we already know how far we need to replay the WAL (up
-		 * minRecoveryPoint, up to backupEndPoint, or until we see an
+		 * to minRecoveryPoint, up to backupEndPoint, or until we see an
 		 * end-of-backup record), and we can enter archive recovery directly.
 		 */
 		if (ArchiveRecoveryRequested &&
@@ -5119,15 +5121,16 @@ StartupXLOG(void)
 	 * timeline in the history of the requested timeline, we cannot proceed:
 	 * the backup is not part of the history of the requested timeline.
 	 */
-	Assert(expectedTLEs); /* was initialized by reading checkpoint record */
+	Assert(expectedTLEs);		/* was initialized by reading checkpoint
+								 * record */
 	if (tliOfPointInHistory(checkPointLoc, expectedTLEs) !=
 		checkPoint.ThisTimeLineID)
 	{
 		XLogRecPtr	switchpoint;
 
 		/*
-		 * tliSwitchPoint will throw an error if the checkpoint's timeline
+		 * tliSwitchPoint will throw an error if the checkpoint's timeline is
-		 * is not in expectedTLEs at all.
+		 * not in expectedTLEs at all.
 		 */
 		switchpoint = tliSwitchPoint(ControlFile->checkPointCopy.ThisTimeLineID, expectedTLEs, NULL);
 		ereport(FATAL,
@@ -5206,16 +5209,16 @@ StartupXLOG(void)
 	ThisTimeLineID = checkPoint.ThisTimeLineID;
 
 	/*
-	 * Copy any missing timeline history files between 'now' and the
+	 * Copy any missing timeline history files between 'now' and the recovery
-	 * recovery target timeline from archive to pg_xlog. While we don't need
+	 * target timeline from archive to pg_xlog. While we don't need those
-	 * those files ourselves - the history file of the recovery target
+	 * files ourselves - the history file of the recovery target timeline
-	 * timeline covers all the previous timelines in the history too - a
+	 * covers all the previous timelines in the history too - a cascading
-	 * cascading standby server might be interested in them. Or, if you
+	 * standby server might be interested in them. Or, if you archive the WAL
-	 * archive the WAL from this server to a different archive than the
+	 * from this server to a different archive than the master, it'd be good
-	 * master, it'd be good for all the history files to get archived there
+	 * for all the history files to get archived there after failover, so that
-	 * after failover, so that you can use one of the old timelines as a
+	 * you can use one of the old timelines as a PITR target. Timeline history
-	 * PITR target. Timeline history files are small, so it's better to copy
+	 * files are small, so it's better to copy them unnecessarily than not
-	 * them unnecessarily than not copy them and regret later.
+	 * copy them and regret later.
 	 */
 	restoreTimeLineHistoryFiles(ThisTimeLineID, recoveryTargetTLI);
 
@@ -5517,6 +5520,7 @@ StartupXLOG(void)
 			do
 			{
 				bool		switchedTLI = false;
+
 #ifdef WAL_DEBUG
 				if (XLOG_DEBUG ||
 				 (rmid == RM_XACT_ID && trace_recovery_messages <= DEBUG2) ||
@@ -5598,13 +5602,13 @@ StartupXLOG(void)
 				}
 
 				/*
-				 * Before replaying this record, check if this record
+				 * Before replaying this record, check if this record causes
-				 * causes the current timeline to change. The record is
+				 * the current timeline to change. The record is already
-				 * already considered to be part of the new timeline,
+				 * considered to be part of the new timeline, so we update
-				 * so we update ThisTimeLineID before replaying it.
+				 * ThisTimeLineID before replaying it. That's important so
-				 * That's important so that replayEndTLI, which is
+				 * that replayEndTLI, which is recorded as the minimum
-				 * recorded as the minimum recovery point's TLI if
+				 * recovery point's TLI if recovery stops after this record,
-				 * recovery stops after this record, is set correctly.
+				 * is set correctly.
 				 */
 				if (record->xl_rmid == RM_XLOG_ID)
 				{
@@ -5952,8 +5956,9 @@ StartupXLOG(void)
 		 * allows some extra error checking in xlog_redo.
 		 *
 		 * In fast promotion, only create a lightweight end-of-recovery record
-		 * instead of a full checkpoint. A checkpoint is requested later, after
+		 * instead of a full checkpoint. A checkpoint is requested later,
-		 * we're fully out of recovery mode and already accepting queries.
+		 * after we're fully out of recovery mode and already accepting
+		 * queries.
 		 */
 		if (bgwriterLaunched)
 		{
@@ -5972,14 +5977,15 @@ StartupXLOG(void)
 					fast_promoted = true;
 
 					/*
-					 * Insert a special WAL record to mark the end of recovery,
+					 * Insert a special WAL record to mark the end of
-					 * since we aren't doing a checkpoint. That means that the
+					 * recovery, since we aren't doing a checkpoint. That
-					 * checkpointer process may likely be in the middle of a
+					 * means that the checkpointer process may likely be in
-					 * time-smoothed restartpoint and could continue to be for
+					 * the middle of a time-smoothed restartpoint and could
-					 * minutes after this. That sounds strange, but the effect
+					 * continue to be for minutes after this. That sounds
-					 * is roughly the same and it would be stranger to try to
+					 * strange, but the effect is roughly the same and it
-					 * come out of the restartpoint and then checkpoint.
+					 * would be stranger to try to come out of the
-					 * We request a checkpoint later anyway, just for safety.
+					 * restartpoint and then checkpoint. We request a
+					 * checkpoint later anyway, just for safety.
 					 */
 					CreateEndOfRecoveryRecord();
 				}
@@ -6092,8 +6098,8 @@ StartupXLOG(void)
 	}
 
 	/*
-	 * If there were cascading standby servers connected to us, nudge any
+	 * If there were cascading standby servers connected to us, nudge any wal
-	 * wal sender processes to notice that we've been promoted.
+	 * sender processes to notice that we've been promoted.
 	 */
 	WalSndWakeup();
 
@@ -6151,9 +6157,9 @@ CheckRecoveryConsistency(void)
 	}
 
 	/*
-	 * Have we passed our safe starting point? Note that minRecoveryPoint
+	 * Have we passed our safe starting point? Note that minRecoveryPoint is
-	 * is known to be incorrectly set if ControlFile->backupEndRequired,
+	 * known to be incorrectly set if ControlFile->backupEndRequired, until
-	 * until the XLOG_BACKUP_RECORD arrives to advise us of the correct
+	 * the XLOG_BACKUP_RECORD arrives to advise us of the correct
 	 * minRecoveryPoint. All we know prior to that is that we're not
 	 * consistent yet.
 	 */
@@ -6946,8 +6952,8 @@ CreateCheckPoint(int flags)
 	TRACE_POSTGRESQL_CHECKPOINT_START(flags);
 
 	/*
-	 * In some cases there are groups of actions that must all occur on
+	 * In some cases there are groups of actions that must all occur on one
-	 * one side or the other of a checkpoint record. Before flushing the
+	 * side or the other of a checkpoint record. Before flushing the
 	 * checkpoint record we must explicitly wait for any backend currently
 	 * performing those groups of actions.
 	 *
@@ -7211,8 +7217,8 @@ CreateEndOfRecoveryRecord(void)
 	XLogFlush(recptr);
 
 	/*
-	 * Update the control file so that crash recovery can follow
+	 * Update the control file so that crash recovery can follow the timeline
-	 * the timeline changes to this point.
+	 * changes to this point.
 	 */
 	LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
 	ControlFile->time = (pg_time_t) xlrec.end_time;
@@ -7458,7 +7464,8 @@ CreateRestartPoint(int flags)
 		XLogRecPtr	endptr;
 
 		/*
-		 * Get the current end of xlog replayed or received, whichever is later.
+		 * Get the current end of xlog replayed or received, whichever is
+		 * later.
 		 */
 		receivePtr = GetWalRcvWriteRecPtr(NULL, NULL);
 		replayPtr = GetXLogReplayRecPtr(NULL);
@@ -7468,8 +7475,8 @@ CreateRestartPoint(int flags)
 		_logSegNo--;
 
 		/*
-		 * Update ThisTimeLineID to the timeline we're currently replaying,
+		 * Update ThisTimeLineID to the timeline we're currently replaying, so
-		 * so that we install any recycled segments on that timeline.
+		 * that we install any recycled segments on that timeline.
 		 *
 		 * There is no guarantee that the WAL segments will be useful on the
 		 * current timeline; if recovery proceeds to a new timeline right
@@ -7480,8 +7487,8 @@ CreateRestartPoint(int flags)
 		 * It's possible or perhaps even likely that we finish recovery while
 		 * a restartpoint is in progress. That means we may get to this point
 		 * some minutes afterwards. Setting ThisTimeLineID at that time would
-		 * actually set it backwards, so we don't want that to persist; if
+		 * actually set it backwards, so we don't want that to persist; if we
-		 * we do reset it here, make sure to reset it back afterwards. This
+		 * do reset it here, make sure to reset it back afterwards. This
 		 * doesn't look very clean or principled, but its the best of about
 		 * five different ways of handling this edge case.
 		 */
@@ -7693,8 +7700,8 @@ XLogSaveBufferForHint(Buffer buffer)
 	GetRedoRecPtr();
 
 	/*
-	 * Setup phony rdata element for use within XLogCheckBuffer only.
+	 * Setup phony rdata element for use within XLogCheckBuffer only. We reuse
-	 * We reuse and reset rdata for any actual WAL record insert.
+	 * and reset rdata for any actual WAL record insert.
 	 */
 	rdata[0].buffer = buffer;
 	rdata[0].buffer_std = true;
@@ -7861,10 +7868,10 @@ checkTimeLineSwitch(XLogRecPtr lsn, TimeLineID newTLI, TimeLineID prevTLI)
 		ereport(PANIC,
 				(errmsg("unexpected prev timeline ID %u (current timeline ID %u) in checkpoint record",
 						prevTLI, ThisTimeLineID)));
+
 	/*
-	 * The new timeline better be in the list of timelines we expect
+	 * The new timeline better be in the list of timelines we expect to see,
-	 * to see, according to the timeline history. It should also not
+	 * according to the timeline history. It should also not decrease.
-	 * decrease.
 	 */
 	if (newTLI < ThisTimeLineID || !tliInHistory(newTLI, expectedTLEs))
 		ereport(PANIC,
@@ -7872,14 +7879,13 @@ checkTimeLineSwitch(XLogRecPtr lsn, TimeLineID newTLI, TimeLineID prevTLI)
 				 newTLI, ThisTimeLineID)));
 
 	/*
-	 * If we have not yet reached min recovery point, and we're about
+	 * If we have not yet reached min recovery point, and we're about to
-	 * to switch to a timeline greater than the timeline of the min
+	 * switch to a timeline greater than the timeline of the min recovery
-	 * recovery point: trouble. After switching to the new timeline,
+	 * point: trouble. After switching to the new timeline, we could not
-	 * we could not possibly visit the min recovery point on the
+	 * possibly visit the min recovery point on the correct timeline anymore.
-	 * correct timeline anymore. This can happen if there is a newer
+	 * This can happen if there is a newer timeline in the archive that
-	 * timeline in the archive that branched before the timeline the
+	 * branched before the timeline the min recovery point is on, and you
-	 * min recovery point is on, and you attempt to do PITR to the
+	 * attempt to do PITR to the new timeline.
-	 * new timeline.
 	 */
 	if (!XLogRecPtrIsInvalid(minRecoveryPoint) &&
 		lsn < minRecoveryPoint &&
@@ -8105,17 +8111,17 @@ xlog_redo(XLogRecPtr lsn, XLogRecord *record)
 		BkpBlock	bkpb;
 
 		/*
-		 * Hint bit records contain a backup block stored "inline" in the normal
+		 * Hint bit records contain a backup block stored "inline" in the
-		 * data since the locking when writing hint records isn't sufficient to
+		 * normal data since the locking when writing hint records isn't
-		 * use the normal backup block mechanism, which assumes exclusive lock
+		 * sufficient to use the normal backup block mechanism, which assumes
-		 * on the buffer supplied.
+		 * exclusive lock on the buffer supplied.
 		 *
-		 * Since the only change in these backup block are hint bits, there are
+		 * Since the only change in these backup block are hint bits, there
-		 * no recovery conflicts generated.
+		 * are no recovery conflicts generated.
 		 *
-		 * This also means there is no corresponding API call for this,
+		 * This also means there is no corresponding API call for this, so an
-		 * so an smgr implementation has no need to implement anything.
+		 * smgr implementation has no need to implement anything. Which means
-		 * Which means nothing is needed in md.c etc
+		 * nothing is needed in md.c etc
 		 */
 		data = XLogRecGetData(record);
 		memcpy(&bkpb, data, sizeof(BkpBlock));
@@ -8379,6 +8385,7 @@ char *
 XLogFileNameP(TimeLineID tli, XLogSegNo segno)
 {
 	char	   *result = palloc(MAXFNAMELEN);
+
 	XLogFileName(result, tli, segno);
 	return result;
 }
@@ -9571,11 +9578,12 @@ WaitForWALToBecomeAvailable(XLogRecPtr RecPtr, bool randAccess,
 					break;
 
 				case XLOG_FROM_PG_XLOG:
+
 					/*
-					 * Check to see if the trigger file exists. Note that we do
+					 * Check to see if the trigger file exists. Note that we
-					 * this only after failure, so when you create the trigger
+					 * do this only after failure, so when you create the
-					 * file, we still finish replaying as much as we can from
+					 * trigger file, we still finish replaying as much as we
-					 * archive and pg_xlog before failover.
+					 * can from archive and pg_xlog before failover.
 					 */
 					if (StandbyMode && CheckForStandbyTrigger())
 					{
@@ -9584,15 +9592,15 @@ WaitForWALToBecomeAvailable(XLogRecPtr RecPtr, bool randAccess,
 					}
 
 					/*
-					 * Not in standby mode, and we've now tried the archive and
+					 * Not in standby mode, and we've now tried the archive
-					 * pg_xlog.
+					 * and pg_xlog.
 					 */
 					if (!StandbyMode)
 						return false;
 
 					/*
-					 * If primary_conninfo is set, launch walreceiver to try to
+					 * If primary_conninfo is set, launch walreceiver to try
-					 * stream the missing WAL.
+					 * to stream the missing WAL.
 					 *
 					 * If fetching_ckpt is TRUE, RecPtr points to the initial
 					 * checkpoint location. In that case, we use RedoStartLSN
@@ -9624,28 +9632,32 @@ WaitForWALToBecomeAvailable(XLogRecPtr RecPtr, bool randAccess,
 						RequestXLogStreaming(tli, ptr, PrimaryConnInfo);
 						receivedUpto = 0;
 					}
+
 					/*
-					 * Move to XLOG_FROM_STREAM state in either case. We'll get
+					 * Move to XLOG_FROM_STREAM state in either case. We'll
-					 * immediate failure if we didn't launch walreceiver, and
+					 * get immediate failure if we didn't launch walreceiver,
-					 * move on to the next state.
+					 * and move on to the next state.
 					 */
 					currentSource = XLOG_FROM_STREAM;
 					break;
 
 				case XLOG_FROM_STREAM:
+
 					/*
-					 * Failure while streaming. Most likely, we got here because
+					 * Failure while streaming. Most likely, we got here
-					 * streaming replication was terminated, or promotion was
+					 * because streaming replication was terminated, or
-					 * triggered. But we also get here if we find an invalid
+					 * promotion was triggered. But we also get here if we
-					 * record in the WAL streamed from master, in which case
+					 * find an invalid record in the WAL streamed from master,
-					 * something is seriously wrong. There's little chance that
+					 * in which case something is seriously wrong. There's
-					 * the problem will just go away, but PANIC is not good for
+					 * little chance that the problem will just go away, but
-					 * availability either, especially in hot standby mode. So,
+					 * PANIC is not good for availability either, especially
-					 * we treat that the same as disconnection, and retry from
+					 * in hot standby mode. So, we treat that the same as
-					 * archive/pg_xlog again. The WAL in the archive should be
+					 * disconnection, and retry from archive/pg_xlog again.
-					 * identical to what was streamed, so it's unlikely that it
+					 * The WAL in the archive should be identical to what was
-					 * helps, but one can hope...
+					 * streamed, so it's unlikely that it helps, but one can
+					 * hope...
 					 */
+
 					/*
 					 * Before we leave XLOG_FROM_STREAM state, make sure that
 					 * walreceiver is not active, so that it won't overwrite
@@ -9668,11 +9680,12 @@ WaitForWALToBecomeAvailable(XLogRecPtr RecPtr, bool randAccess,
 					}
 
 					/*
-					 * XLOG_FROM_STREAM is the last state in our state machine,
+					 * XLOG_FROM_STREAM is the last state in our state
-					 * so we've exhausted all the options for obtaining the
+					 * machine, so we've exhausted all the options for
-					 * requested WAL. We're going to loop back and retry from
+					 * obtaining the requested WAL. We're going to loop back
-					 * the archive, but if it hasn't been long since last
+					 * and retry from the archive, but if it hasn't been long
-					 * attempt, sleep 5 seconds to avoid busy-waiting.
+					 * since last attempt, sleep 5 seconds to avoid
+					 * busy-waiting.
 					 */
 					now = (pg_time_t) time(NULL);
 					if ((now - last_fail_time) < 5)
@@ -9691,9 +9704,9 @@ WaitForWALToBecomeAvailable(XLogRecPtr RecPtr, bool randAccess,
 		else if (currentSource == XLOG_FROM_PG_XLOG)
 		{
 			/*
-			 * We just successfully read a file in pg_xlog. We prefer files
+			 * We just successfully read a file in pg_xlog. We prefer files in
-			 * in the archive over ones in pg_xlog, so try the next file
+			 * the archive over ones in pg_xlog, so try the next file again
-			 * again from the archive first.
+			 * from the archive first.
 			 */
 			if (InArchiveRecovery)
 				currentSource = XLOG_FROM_ARCHIVE;
@@ -9754,13 +9767,14 @@ WaitForWALToBecomeAvailable(XLogRecPtr RecPtr, bool randAccess,
 					/*
 					 * Walreceiver is active, so see if new data has arrived.
 					 *
-				 * We only advance XLogReceiptTime when we obtain fresh WAL
+					 * We only advance XLogReceiptTime when we obtain fresh
-				 * from walreceiver and observe that we had already processed
+					 * WAL from walreceiver and observe that we had already
-				 * everything before the most recent "chunk" that it flushed to
+					 * processed everything before the most recent "chunk"
-				 * disk.  In steady state where we are keeping up with the
+					 * that it flushed to disk.  In steady state where we are
-				 * incoming data, XLogReceiptTime will be updated on each cycle.
+					 * keeping up with the incoming data, XLogReceiptTime will
-				 * When we are behind, XLogReceiptTime will not advance, so the
+					 * be updated on each cycle. When we are behind,
-				 * grace time allotted to conflicting queries will decrease.
+					 * XLogReceiptTime will not advance, so the grace time
+					 * allotted to conflicting queries will decrease.
 					 */
 					if (RecPtr < receivedUpto)
 						havedata = true;
@@ -9784,12 +9798,13 @@ WaitForWALToBecomeAvailable(XLogRecPtr RecPtr, bool randAccess,
 					if (havedata)
 					{
 						/*
-					 * Great, streamed far enough.  Open the file if it's not
+						 * Great, streamed far enough.	Open the file if it's
-					 * open already.  Also read the timeline history file if
+						 * not open already.  Also read the timeline history
-					 * we haven't initialized timeline history yet; it should
+						 * file if we haven't initialized timeline history
-					 * be streamed over and present in pg_xlog by now.  Use
+						 * yet; it should be streamed over and present in
-					 * XLOG_FROM_STREAM so that source info is set correctly
+						 * pg_xlog by now.	Use XLOG_FROM_STREAM so that
-					 * and XLogReceiptTime isn't changed.
+						 * source info is set correctly and XLogReceiptTime
+						 * isn't changed.
 						 */
 						if (readFile < 0)
 						{
@@ -9818,20 +9833,21 @@ WaitForWALToBecomeAvailable(XLogRecPtr RecPtr, bool randAccess,
 					{
 						/*
 						 * Note that we don't "return false" immediately here.
-					 * After being triggered, we still want to replay all the
+						 * After being triggered, we still want to replay all
-					 * WAL that was already streamed. It's in pg_xlog now, so
+						 * the WAL that was already streamed. It's in pg_xlog
-					 * we just treat this as a failure, and the state machine
+						 * now, so we just treat this as a failure, and the
-					 * will move on to replay the streamed WAL from pg_xlog,
+						 * state machine will move on to replay the streamed
-					 * and then recheck the trigger and exit replay.
+						 * WAL from pg_xlog, and then recheck the trigger and
+						 * exit replay.
 						 */
 						lastSourceFailed = true;
 						break;
 					}
 
 					/*
-				 * Wait for more WAL to arrive. Time out after 5 seconds, like
+					 * Wait for more WAL to arrive. Time out after 5 seconds,
-				 * when polling the archive, to react to a trigger file
+					 * like when polling the archive, to react to a trigger
-				 * promptly.
+					 * file promptly.
 					 */
 					WaitLatch(&XLogCtl->recoveryWakeupLatch,
 							  WL_LATCH_SET | WL_TIMEOUT,
@@ -9903,11 +9919,10 @@ CheckForStandbyTrigger(void)
 	if (IsPromoteTriggered())
 	{
 		/*
-		 * In 9.1 and 9.2 the postmaster unlinked the promote file
+		 * In 9.1 and 9.2 the postmaster unlinked the promote file inside the
-		 * inside the signal handler. We now leave the file in place
+		 * signal handler. We now leave the file in place and let the Startup
-		 * and let the Startup process do the unlink. This allows
+		 * process do the unlink. This allows Startup to know whether we're
-		 * Startup to know whether we're doing fast or normal
+		 * doing fast or normal promotion. Fast promotion takes precedence.
-		 * promotion. Fast promotion takes precedence.
 		 */
 		if (stat(FAST_PROMOTE_SIGNAL_FILE, &stat_buf) == 0)
 		{

src/backend/access/transam/xlogarchive.c

@@ -87,9 +87,9 @@ RestoreArchivedFile(char *path, const char *xlogfname,
 	 * of log segments that weren't yet transferred to the archive.
 	 *
 	 * Notice that we don't actually overwrite any files when we copy back
-	 * from archive because the restore_command may inadvertently
+	 * from archive because the restore_command may inadvertently restore
-	 * restore inappropriate xlogs, or they may be corrupt, so we may wish to
+	 * inappropriate xlogs, or they may be corrupt, so we may wish to fallback
-	 * fallback to the segments remaining in current XLOGDIR later. The
+	 * to the segments remaining in current XLOGDIR later. The
 	 * copy-from-archive filename is always the same, ensuring that we don't
 	 * run out of disk space on long recoveries.
 	 */
@@ -434,18 +434,19 @@ KeepFileRestoredFromArchive(char *path, char *xlogfname)
 	if (stat(xlogfpath, &statbuf) == 0)
 	{
 		char		oldpath[MAXPGPATH];
+
 #ifdef WIN32
 		static unsigned int deletedcounter = 1;
+
 		/*
-		 * On Windows, if another process (e.g a walsender process) holds
+		 * On Windows, if another process (e.g a walsender process) holds the
-		 * the file open in FILE_SHARE_DELETE mode, unlink will succeed,
+		 * file open in FILE_SHARE_DELETE mode, unlink will succeed, but the
-		 * but the file will still show up in directory listing until the
+		 * file will still show up in directory listing until the last handle
-		 * last handle is closed, and we cannot rename the new file in its
+		 * is closed, and we cannot rename the new file in its place until
-		 * place until that. To avoid that problem, rename the old file to
+		 * that. To avoid that problem, rename the old file to a temporary
-		 * a temporary name first. Use a counter to create a unique
+		 * name first. Use a counter to create a unique filename, because the
-		 * filename, because the same file might be restored from the
+		 * same file might be restored from the archive multiple times, and a
-		 * archive multiple times, and a walsender could still be holding
+		 * walsender could still be holding onto an old deleted version of it.
-		 * onto an old deleted version of it.
 		 */
 		snprintf(oldpath, MAXPGPATH, "%s.deleted%u",
 				 xlogfpath, deletedcounter++);
@@ -474,17 +475,17 @@ KeepFileRestoredFromArchive(char *path, char *xlogfname)
 						path, xlogfpath)));
 
 	/*
-	 * Create .done file forcibly to prevent the restored segment from
+	 * Create .done file forcibly to prevent the restored segment from being
-	 * being archived again later.
+	 * archived again later.
 	 */
 	XLogArchiveForceDone(xlogfname);
 
 	/*
-	 * If the existing file was replaced, since walsenders might have it
+	 * If the existing file was replaced, since walsenders might have it open,
-	 * open, request them to reload a currently-open segment. This is only
+	 * request them to reload a currently-open segment. This is only required
-	 * required for WAL segments, walsenders don't hold other files open, but
+	 * for WAL segments, walsenders don't hold other files open, but there's
-	 * there's no harm in doing this too often, and we don't know what kind
+	 * no harm in doing this too often, and we don't know what kind of a file
-	 * of a file we're dealing with here.
+	 * we're dealing with here.
 	 */
 	if (reload)
 		WalSndRqstFileReload();

src/backend/access/transam/xlogreader.c

@@ -221,9 +221,9 @@ XLogReadRecord(XLogReaderState *state, XLogRecPtr RecPtr, char **errormsg)
 	targetRecOff = RecPtr % XLOG_BLCKSZ;
 
 	/*
-	 * Read the page containing the record into state->readBuf. Request
+	 * Read the page containing the record into state->readBuf. Request enough
-	 * enough byte to cover the whole record header, or at least the part of
+	 * byte to cover the whole record header, or at least the part of it that
-	 * it that fits on the same page.
+	 * fits on the same page.
 	 */
 	readOff = ReadPageInternal(state,
 							   targetPagePtr,

src/backend/catalog/heap.c

@@ -870,6 +870,7 @@ AddNewRelationTuple(Relation pg_class_desc,
 		 * that will do.
 		 */
 		new_rel_reltup->relfrozenxid = RecentXmin;
+
 		/*
 		 * Similarly, initialize the minimum Multixact to the first value that
 		 * could possibly be stored in tuples in the table.  Running
@@ -1915,10 +1916,10 @@ StoreAttrDefault(Relation rel, AttrNumber attnum,
 	/*
 	 * Post creation hook for attribute defaults.
 	 *
-	 * XXX. ALTER TABLE ALTER COLUMN SET/DROP DEFAULT is implemented
+	 * XXX. ALTER TABLE ALTER COLUMN SET/DROP DEFAULT is implemented with a
-	 * with a couple of deletion/creation of the attribute's default entry,
+	 * couple of deletion/creation of the attribute's default entry, so the
-	 * so the callee should check existence of an older version of this
+	 * callee should check existence of an older version of this entry if it
-	 * entry if it needs to distinguish.
+	 * needs to distinguish.
 	 */
 	InvokeObjectPostCreateHookArg(AttrDefaultRelationId,
 								  RelationGetRelid(rel), attnum, is_internal);

src/backend/catalog/namespace.c

@@ -293,6 +293,7 @@ RangeVarGetRelidExtended(const RangeVar *relation, LOCKMODE lockmode,
 					Oid			namespaceId;
 
 					namespaceId = LookupExplicitNamespace(relation->schemaname, missing_ok);
+
 					/*
 					 * For missing_ok, allow a non-existant schema name to
 					 * return InvalidOid.

src/backend/catalog/objectaddress.c

@@ -94,10 +94,11 @@ typedef struct
 	AttrNumber	attnum_owner;	/* attnum of owner field */
 	AttrNumber	attnum_acl;		/* attnum of acl field */
 	AclObjectKind acl_kind;		/* ACL_KIND_* of this object type */
-	bool		is_nsp_name_unique;	/* can the nsp/name combination (or name
+	bool		is_nsp_name_unique;		/* can the nsp/name combination (or
-									 * alone, if there's no namespace) be
+										 * name alone, if there's no
-									 * considered an unique identifier for an
+										 * namespace) be considered an unique
-									 * object of this class? */
+										 * identifier for an object of this
+										 * class? */
 } ObjectPropertyType;
 
 static ObjectPropertyType ObjectProperty[] =
@@ -2359,8 +2360,8 @@ pg_identify_object(PG_FUNCTION_ARGS)
 			}
 
 			/*
-			 * We only return the object name if it can be used (together
+			 * We only return the object name if it can be used (together with
-			 * with the schema name, if any) as an unique identifier.
+			 * the schema name, if any) as an unique identifier.
 			 */
 			if (get_object_namensp_unique(address.classId))
 			{

src/backend/catalog/pg_operator.c

@@ -92,11 +92,11 @@ validOperatorName(const char *name)
 		return false;
 
 	/*
-	 * For SQL standard compatibility, '+' and '-' cannot be the last char of a
+	 * For SQL standard compatibility, '+' and '-' cannot be the last char of
-	 * multi-char operator unless the operator contains chars that are not in
+	 * a multi-char operator unless the operator contains chars that are not
-	 * SQL operators. The idea is to lex '=-' as two operators, but not to
+	 * in SQL operators. The idea is to lex '=-' as two operators, but not to
-	 * forbid operator names like '?-' that could not be sequences of standard SQL
+	 * forbid operator names like '?-' that could not be sequences of standard
-	 * operators.
+	 * SQL operators.
 	 */
 	if (len > 1 &&
 		(name[len - 1] == '+' ||

src/backend/catalog/storage.c

@@ -505,13 +505,12 @@ smgr_redo(XLogRecPtr lsn, XLogRecord *record)
 		smgrcreate(reln, MAIN_FORKNUM, true);
 
 		/*
-		 * Before we perform the truncation, update minimum recovery point
+		 * Before we perform the truncation, update minimum recovery point to
-		 * to cover this WAL record. Once the relation is truncated, there's
+		 * cover this WAL record. Once the relation is truncated, there's no
-		 * no going back. The buffer manager enforces the WAL-first rule
+		 * going back. The buffer manager enforces the WAL-first rule for
-		 * for normal updates to relation files, so that the minimum recovery
+		 * normal updates to relation files, so that the minimum recovery
-		 * point is always updated before the corresponding change in the
+		 * point is always updated before the corresponding change in the data
-		 * data file is flushed to disk. We have to do the same manually
+		 * file is flushed to disk. We have to do the same manually here.
-		 * here.
 		 *
 		 * Doing this before the truncation means that if the truncation fails
 		 * for some reason, you cannot start up the system even after restart,

src/backend/commands/copy.c

@@ -501,9 +501,9 @@ CopySendEndOfRow(CopyState cstate)
 						ClosePipeToProgram(cstate);
 
 						/*
-						 * If ClosePipeToProgram() didn't throw an error,
+						 * If ClosePipeToProgram() didn't throw an error, the
-						 * the program terminated normally, but closed the
+						 * program terminated normally, but closed the pipe
-						 * pipe first. Restore errno, and throw an error.
+						 * first. Restore errno, and throw an error.
 						 */
 						errno = EPIPE;
 					}
@@ -1022,9 +1022,9 @@ ProcessCopyOptions(CopyState cstate,
 		else if (strcmp(defel->defname, "convert_selectively") == 0)
 		{
 			/*
-			 * Undocumented, not-accessible-from-SQL option: convert only
+			 * Undocumented, not-accessible-from-SQL option: convert only the
-			 * the named columns to binary form, storing the rest as NULLs.
+			 * named columns to binary form, storing the rest as NULLs. It's
-			 * It's allowed for the column list to be NIL.
+			 * allowed for the column list to be NIL.
 			 */
 			if (cstate->convert_selectively)
 				ereport(ERROR,
@@ -1929,8 +1929,8 @@ CopyFromErrorCallback(void *arg)
 			 * Error is relevant to a particular line.
 			 *
 			 * If line_buf still contains the correct line, and it's already
-			 * transcoded, print it. If it's still in a foreign encoding,
+			 * transcoded, print it. If it's still in a foreign encoding, it's
-			 * it's quite likely that the error is precisely a failure to do
+			 * quite likely that the error is precisely a failure to do
 			 * encoding conversion (ie, bad data). We dare not try to convert
 			 * it, and at present there's no way to regurgitate it without
 			 * conversion. So we have to punt and just report the line number.
@@ -2096,13 +2096,12 @@ CopyFrom(CopyState cstate)
 	}
 
 	/*
-	 * Optimize if new relfilenode was created in this subxact or
+	 * Optimize if new relfilenode was created in this subxact or one of its
-	 * one of its committed children and we won't see those rows later
+	 * committed children and we won't see those rows later as part of an
-	 * as part of an earlier scan or command. This ensures that if this
+	 * earlier scan or command. This ensures that if this subtransaction
-	 * subtransaction aborts then the frozen rows won't be visible
+	 * aborts then the frozen rows won't be visible after xact cleanup. Note
-	 * after xact cleanup. Note that the stronger test of exactly
+	 * that the stronger test of exactly which subtransaction created it is
-	 * which subtransaction created it is crucial for correctness
+	 * crucial for correctness of this optimisation.
-	 * of this optimisation.
 	 */
 	if (cstate->freeze)
 	{

src/backend/commands/dbcommands.c

@@ -1882,8 +1882,11 @@ static int
 errdetail_busy_db(int notherbackends, int npreparedxacts)
 {
 	if (notherbackends > 0 && npreparedxacts > 0)
-		/* We don't deal with singular versus plural here, since gettext
+
-		 * doesn't support multiple plurals in one string. */
+		/*
+		 * We don't deal with singular versus plural here, since gettext
+		 * doesn't support multiple plurals in one string.
+		 */
 		errdetail("There are %d other session(s) and %d prepared transaction(s) using the database.",
 				  notherbackends, npreparedxacts);
 	else if (notherbackends > 0)

src/backend/commands/event_trigger.c

@@ -302,7 +302,8 @@ insert_event_trigger_tuple(char *trigname, char *eventname, Oid evtOwner,
 	HeapTuple	tuple;
 	Datum		values[Natts_pg_trigger];
 	bool		nulls[Natts_pg_trigger];
-	ObjectAddress myself, referenced;
+	ObjectAddress myself,
+				referenced;
 
 	/* Open pg_event_trigger. */
 	tgrel = heap_open(EventTriggerRelationId, RowExclusiveLock);
@@ -646,11 +647,11 @@ EventTriggerCommonSetup(Node *parsetree,
 	tag = CreateCommandTag(parsetree);
 
 	/*
-	 * Filter list of event triggers by command tag, and copy them into
+	 * Filter list of event triggers by command tag, and copy them into our
-	 * our memory context.  Once we start running the command trigers, or
+	 * memory context.	Once we start running the command trigers, or indeed
-	 * indeed once we do anything at all that touches the catalogs, an
+	 * once we do anything at all that touches the catalogs, an invalidation
-	 * invalidation might leave cachelist pointing at garbage, so we must
+	 * might leave cachelist pointing at garbage, so we must do this before we
-	 * do this before we can do much else.
+	 * can do much else.
 	 */
 	foreach(lc, cachelist)
 	{
@@ -716,8 +717,8 @@ EventTriggerDDLCommandStart(Node *parsetree)
 	list_free(runlist);
 
 	/*
-	 * Make sure anything the event triggers did will be visible to
+	 * Make sure anything the event triggers did will be visible to the main
-	 * the main command.
+	 * command.
 	 */
 	CommandCounterIncrement();
 }
@@ -745,8 +746,8 @@ EventTriggerDDLCommandEnd(Node *parsetree)
 		return;
 
 	/*
-	 * Make sure anything the main command did will be visible to the
+	 * Make sure anything the main command did will be visible to the event
-	 * event triggers.
+	 * triggers.
 	 */
 	CommandCounterIncrement();
 
@@ -774,10 +775,11 @@ EventTriggerSQLDrop(Node *parsetree)
 		return;
 
 	/*
-	 * Use current state to determine whether this event fires at all.  If there
+	 * Use current state to determine whether this event fires at all.	If
-	 * are no triggers for the sql_drop event, then we don't have anything to do
+	 * there are no triggers for the sql_drop event, then we don't have
-	 * here.  Note that dropped object collection is disabled if this is the case,
+	 * anything to do here.  Note that dropped object collection is disabled
-	 * so even if we were to try to run, the list would be empty.
+	 * if this is the case, so even if we were to try to run, the list would
+	 * be empty.
 	 */
 	if (!currentEventTriggerState ||
 		slist_is_empty(&currentEventTriggerState->SQLDropList))
@@ -786,24 +788,25 @@ EventTriggerSQLDrop(Node *parsetree)
 	runlist = EventTriggerCommonSetup(parsetree,
 									  EVT_SQLDrop, "sql_drop",
 									  &trigdata);
+
 	/*
-	 * Nothing to do if run list is empty.  Note this shouldn't happen, because
+	 * Nothing to do if run list is empty.	Note this shouldn't happen,
-	 * if there are no sql_drop events, then objects-to-drop wouldn't have been
+	 * because if there are no sql_drop events, then objects-to-drop wouldn't
-	 * collected in the first place and we would have quitted above.
+	 * have been collected in the first place and we would have quitted above.
 	 */
 	if (runlist == NIL)
 		return;
 
 	/*
-	 * Make sure anything the main command did will be visible to the
+	 * Make sure anything the main command did will be visible to the event
-	 * event triggers.
+	 * triggers.
 	 */
 	CommandCounterIncrement();
 
 	/*
-	 * Make sure pg_event_trigger_dropped_objects only works when running these
+	 * Make sure pg_event_trigger_dropped_objects only works when running
-	 * triggers.  Use PG_TRY to ensure in_sql_drop is reset even when one
+	 * these triggers.	Use PG_TRY to ensure in_sql_drop is reset even when
-	 * trigger fails.  (This is perhaps not necessary, as the currentState
+	 * one trigger fails.  (This is perhaps not necessary, as the currentState
 	 * variable will be removed shortly by our caller, but it seems better to
 	 * play safe.)
 	 */
@@ -841,8 +844,8 @@ EventTriggerInvoke(List *fn_oid_list, EventTriggerData *trigdata)
 	check_stack_depth();
 
 	/*
-	 * Let's evaluate event triggers in their own memory context, so
+	 * Let's evaluate event triggers in their own memory context, so that any
-	 * that any leaks get cleaned up promptly.
+	 * leaks get cleaned up promptly.
 	 */
 	context = AllocSetContextCreate(CurrentMemoryContext,
 									"event trigger context",
@@ -860,10 +863,10 @@ EventTriggerInvoke(List *fn_oid_list, EventTriggerData *trigdata)
 		PgStat_FunctionCallUsage fcusage;
 
 		/*
-		 * We want each event trigger to be able to see the results of
+		 * We want each event trigger to be able to see the results of the
-		 * the previous event trigger's action.  Caller is responsible
+		 * previous event trigger's action.  Caller is responsible for any
-		 * for any command-counter increment that is needed between the
+		 * command-counter increment that is needed between the event trigger
-		 * event trigger and anything else in the transaction.
+		 * and anything else in the transaction.
 		 */
 		if (first)
 			first = false;
@@ -987,6 +990,7 @@ EventTriggerSupportsObjectClass(ObjectClass objclass)
 			return true;
 
 		case MAX_OCLASS:
+
 			/*
 			 * This shouldn't ever happen, but we keep the case to avoid a
 			 * compiler warning without a "default" clause in the switch.
@@ -1112,8 +1116,9 @@ EventTriggerSQLDropAddObject(ObjectAddress *object)
 
 	/*
 	 * Obtain schema names from the object's catalog tuple, if one exists;
-	 * this lets us skip objects in temp schemas.  We trust that ObjectProperty
+	 * this lets us skip objects in temp schemas.  We trust that
-	 * contains all object classes that can be schema-qualified.
+	 * ObjectProperty contains all object classes that can be
+	 * schema-qualified.
 	 */
 	if (is_objectclass_supported(object->classId))
 	{

src/backend/commands/explain.c

@@ -415,8 +415,8 @@ ExplainOnePlan(PlannedStmt *plannedstmt, IntoClause *into, ExplainState *es,
 		instrument_option |= INSTRUMENT_BUFFERS;
 
 	/*
-	 * We always collect timing for the entire statement, even when
+	 * We always collect timing for the entire statement, even when node-level
-	 * node-level timing is off, so we don't look at es->timing here.
+	 * timing is off, so we don't look at es->timing here.
 	 */
 	INSTR_TIME_SET_CURRENT(starttime);
 

src/backend/commands/sequence.c

@@ -698,8 +698,8 @@ nextval_internal(Oid relid)
 	/*
 	 * We must mark the buffer dirty before doing XLogInsert(); see notes in
 	 * SyncOneBuffer().  However, we don't apply the desired changes just yet.
-	 * This looks like a violation of the buffer update protocol, but it is
+	 * This looks like a violation of the buffer update protocol, but it is in
-	 * in fact safe because we hold exclusive lock on the buffer.  Any other
+	 * fact safe because we hold exclusive lock on the buffer.	Any other
 	 * process, including a checkpoint, that tries to examine the buffer
 	 * contents will block until we release the lock, and then will see the
 	 * final state that we install below.
@@ -1226,8 +1226,8 @@ init_params(List *options, bool isInit,
 	}
 
 	/*
-	 * We must reset log_cnt when isInit or when changing any parameters
+	 * We must reset log_cnt when isInit or when changing any parameters that
-	 * that would affect future nextval allocations.
+	 * would affect future nextval allocations.
 	 */
 	if (isInit)
 		new->log_cnt = 0;

src/backend/commands/tablecmds.c

@@ -1675,9 +1675,9 @@ MergeAttributes(List *schema, List *supers, char relpersistence,
 										   &found_whole_row);
 
 				/*
-				 * For the moment we have to reject whole-row variables.
+				 * For the moment we have to reject whole-row variables. We
-				 * We could convert them, if we knew the new table's rowtype
+				 * could convert them, if we knew the new table's rowtype OID,
-				 * OID, but that hasn't been assigned yet.
+				 * but that hasn't been assigned yet.
 				 */
 				if (found_whole_row)
 					ereport(ERROR,
@@ -3294,7 +3294,8 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab, Relation rel,
 			ATExecAddConstraint(wqueue, tab, rel, (Constraint *) cmd->def,
 								true, false, lockmode);
 			break;
-		case AT_ReAddConstraint:	/* Re-add pre-existing check constraint */
+		case AT_ReAddConstraint:		/* Re-add pre-existing check
+										 * constraint */
 			ATExecAddConstraint(wqueue, tab, rel, (Constraint *) cmd->def,
 								false, true, lockmode);
 			break;
@@ -9564,9 +9565,9 @@ ATExecDropInherit(Relation rel, RangeVar *parent, LOCKMODE lockmode)
 						   RelationGetRelid(parent_rel));
 
 	/*
-	 * Post alter hook of this inherits. Since object_access_hook doesn't
+	 * Post alter hook of this inherits. Since object_access_hook doesn't take
-	 * take multiple object identifiers, we relay oid of parent relation
+	 * multiple object identifiers, we relay oid of parent relation using
-	 * using auxiliary_id argument.
+	 * auxiliary_id argument.
 	 */
 	InvokeObjectPostAlterHookArg(InheritsRelationId,
 								 RelationGetRelid(rel), 0,
@@ -10247,6 +10248,7 @@ PreCommit_on_commit_actions(void)
 				/* Do nothing (there shouldn't be such entries, actually) */
 				break;
 			case ONCOMMIT_DELETE_ROWS:
+
 				/*
 				 * If this transaction hasn't accessed any temporary
 				 * relations, we can skip truncating ON COMMIT DELETE ROWS

src/backend/commands/trigger.c

@@ -1266,6 +1266,7 @@ renametrig(RenameStmt *stmt)
 	if (HeapTupleIsValid(tuple = systable_getnext(tgscan)))
 	{
 		tgoid = HeapTupleGetOid(tuple);
+
 		/*
 		 * Update pg_trigger tuple with new tgname.
 		 */
@@ -2619,6 +2620,7 @@ ltrmark:;
 		switch (test)
 		{
 			case HeapTupleSelfUpdated:
+
 				/*
 				 * The target tuple was already updated or deleted by the
 				 * current command, or by a later command in the current

src/backend/commands/typecmds.c

@@ -924,8 +924,8 @@ DefineDomain(CreateDomainStmt *stmt)
 				/*
 				 * Check constraints are handled after domain creation, as
 				 * they require the Oid of the domain; at this point we can
-				 * only check that they're not marked NO INHERIT, because
+				 * only check that they're not marked NO INHERIT, because that
-				 * that would be bogus.
+				 * would be bogus.
 				 */
 				if (constr->is_no_inherit)
 					ereport(ERROR,
@@ -1192,14 +1192,14 @@ AlterEnum(AlterEnumStmt *stmt, bool isTopLevel)
 	 * Ordinarily we disallow adding values within transaction blocks, because
 	 * we can't cope with enum OID values getting into indexes and then having
 	 * their defining pg_enum entries go away.	However, it's okay if the enum
-	 * type was created in the current transaction, since then there can be
+	 * type was created in the current transaction, since then there can be no
-	 * no such indexes that wouldn't themselves go away on rollback.  (We
+	 * such indexes that wouldn't themselves go away on rollback.  (We support
-	 * support this case because pg_dump --binary-upgrade needs it.)  We test
+	 * this case because pg_dump --binary-upgrade needs it.)  We test this by
-	 * this by seeing if the pg_type row has xmin == current XID and is not
+	 * seeing if the pg_type row has xmin == current XID and is not
-	 * HEAP_UPDATED.  If it is HEAP_UPDATED, we can't be sure whether the
+	 * HEAP_UPDATED.  If it is HEAP_UPDATED, we can't be sure whether the type
-	 * type was created or only modified in this xact.  So we are disallowing
+	 * was created or only modified in this xact.  So we are disallowing some
-	 * some cases that could theoretically be safe; but fortunately pg_dump
+	 * cases that could theoretically be safe; but fortunately pg_dump only
-	 * only needs the simplest case.
+	 * needs the simplest case.
 	 */
 	if (HeapTupleHeaderGetXmin(tup->t_data) == GetCurrentTransactionId() &&
 		!(tup->t_data->t_infomask & HEAP_UPDATED))

src/backend/commands/vacuum.c

@@ -327,10 +327,10 @@ get_rel_oids(Oid relid, const RangeVar *vacrel)
 		 * Since we don't take a lock here, the relation might be gone, or the
 		 * RangeVar might no longer refer to the OID we look up here.  In the
 		 * former case, VACUUM will do nothing; in the latter case, it will
-		 * process the OID we looked up here, rather than the new one.
+		 * process the OID we looked up here, rather than the new one. Neither
-		 * Neither is ideal, but there's little practical alternative, since
+		 * is ideal, but there's little practical alternative, since we're
-		 * we're going to commit this transaction and begin a new one between
+		 * going to commit this transaction and begin a new one between now
-		 * now and then.
+		 * and then.
 		 */
 		relid = RangeVarGetRelid(vacrel, NoLock, false);
 
@@ -723,8 +723,8 @@ vac_update_datfrozenxid(void)
 	newFrozenXid = GetOldestXmin(true, true);
 
 	/*
-	 * Similarly, initialize the MultiXact "min" with the value that would
+	 * Similarly, initialize the MultiXact "min" with the value that would be
-	 * be used on pg_class for new tables.  See AddNewRelationTuple().
+	 * used on pg_class for new tables.  See AddNewRelationTuple().
 	 */
 	newFrozenMulti = GetOldestMultiXactId();
 
@@ -900,8 +900,8 @@ vac_truncate_clog(TransactionId frozenXID, MultiXactId frozenMulti)
 
 	/*
 	 * Update the wrap limit for GetNewTransactionId and creation of new
-	 * MultiXactIds.  Note: these functions will also signal the postmaster for
+	 * MultiXactIds.  Note: these functions will also signal the postmaster
-	 * an(other) autovac cycle if needed.   XXX should we avoid possibly
+	 * for an(other) autovac cycle if needed.	XXX should we avoid possibly
 	 * signalling twice?
 	 */
 	SetTransactionIdLimit(frozenXID, oldestxid_datoid);

src/backend/commands/vacuumlazy.c

@@ -903,11 +903,11 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
 			 * so that we get back in sync.
 			 *
 			 * NB: If the heap page is all-visible but the VM bit is not set,
-			 * we don't need to dirty the heap page.  However, if checksums are
+			 * we don't need to dirty the heap page.  However, if checksums
-			 * enabled, we do need to make sure that the heap page is dirtied
+			 * are enabled, we do need to make sure that the heap page is
-			 * before passing it to visibilitymap_set(), because it may be
+			 * dirtied before passing it to visibilitymap_set(), because it
-			 * logged.  Given that this situation should only happen in rare
+			 * may be logged.  Given that this situation should only happen in
-			 * cases after a crash, it is not worth optimizing.
+			 * rare cases after a crash, it is not worth optimizing.
 			 */
 			PageSetAllVisible(page);
 			MarkBufferDirty(buf);
@@ -1146,8 +1146,8 @@ lazy_vacuum_page(Relation onerel, BlockNumber blkno, Buffer buffer,
 	MarkBufferDirty(buffer);
 
 	/*
-	 * Now that we have removed the dead tuples from the page, once again check
+	 * Now that we have removed the dead tuples from the page, once again
-	 * if the page has become all-visible.
+	 * check if the page has become all-visible.
 	 */
 	if (!visibilitymap_test(onerel, blkno, vmbuffer) &&
 		heap_page_is_all_visible(buffer, &visibility_cutoff_xid))
@@ -1669,8 +1669,7 @@ heap_page_is_all_visible(Buffer buf, TransactionId *visibility_cutoff_xid)
 
 	/*
 	 * This is a stripped down version of the line pointer scan in
-	 * lazy_scan_heap(). So if you change anything here, also check that
+	 * lazy_scan_heap(). So if you change anything here, also check that code.
-	 * code.
 	 */
 	maxoff = PageGetMaxOffsetNumber(page);
 	for (offnum = FirstOffsetNumber;
@@ -1689,8 +1688,8 @@ heap_page_is_all_visible(Buffer buf, TransactionId *visibility_cutoff_xid)
 		ItemPointerSet(&(tuple.t_self), BufferGetBlockNumber(buf), offnum);
 
 		/*
-		 * Dead line pointers can have index pointers pointing to them. So they
+		 * Dead line pointers can have index pointers pointing to them. So
-		 * can't be treated as visible
+		 * they can't be treated as visible
 		 */
 		if (ItemIdIsDead(itemid))
 		{
@@ -1716,8 +1715,8 @@ heap_page_is_all_visible(Buffer buf, TransactionId *visibility_cutoff_xid)
 					}
 
 					/*
-					 * The inserter definitely committed. But is it old
+					 * The inserter definitely committed. But is it old enough
-					 * enough that everyone sees it as committed?
+					 * that everyone sees it as committed?
 					 */
 					xmin = HeapTupleHeaderGetXmin(tuple.t_data);
 					if (!TransactionIdPrecedes(xmin, OldestXmin))

src/backend/executor/execMain.c

@@ -959,12 +959,13 @@ CheckValidResultRel(Relation resultRel, CmdType operation)
 							RelationGetRelationName(resultRel))));
 			break;
 		case RELKIND_VIEW:
+
 			/*
 			 * Okay only if there's a suitable INSTEAD OF trigger.  Messages
 			 * here should match rewriteHandler.c's rewriteTargetView, except
 			 * that we omit errdetail because we haven't got the information
-			 * handy (and given that we really shouldn't get here anyway,
+			 * handy (and given that we really shouldn't get here anyway, it's
-			 * it's not worth great exertion to get).
+			 * not worth great exertion to get).
 			 */
 			switch (operation)
 			{
@@ -1391,7 +1392,8 @@ ExecEndPlan(PlanState *planstate, EState *estate)
 	}
 
 	/*
-	 * close any relations selected FOR [KEY] UPDATE/SHARE, again keeping locks
+	 * close any relations selected FOR [KEY] UPDATE/SHARE, again keeping
+	 * locks
 	 */
 	foreach(l, estate->es_rowMarks)
 	{
@@ -1546,9 +1548,9 @@ ExecRelCheck(ResultRelInfo *resultRelInfo,
 		qual = resultRelInfo->ri_ConstraintExprs[i];
 
 		/*
-		 * NOTE: SQL specifies that a NULL result from a constraint
+		 * NOTE: SQL specifies that a NULL result from a constraint expression
-		 * expression is not to be treated as a failure.  Therefore, tell
+		 * is not to be treated as a failure.  Therefore, tell ExecQual to
-		 * ExecQual to return TRUE for NULL.
+		 * return TRUE for NULL.
 		 */
 		if (!ExecQual(qual, econtext, true))
 			return check[i].ccname;
@@ -1901,13 +1903,13 @@ EvalPlanQualFetch(EState *estate, Relation relation, int lockmode,
 			/*
 			 * If tuple was inserted by our own transaction, we have to check
 			 * cmin against es_output_cid: cmin >= current CID means our
-			 * command cannot see the tuple, so we should ignore it.
+			 * command cannot see the tuple, so we should ignore it. Otherwise
-			 * Otherwise heap_lock_tuple() will throw an error, and so would
+			 * heap_lock_tuple() will throw an error, and so would any later
-			 * any later attempt to update or delete the tuple.  (We need not
+			 * attempt to update or delete the tuple.  (We need not check cmax
-			 * check cmax because HeapTupleSatisfiesDirty will consider a
+			 * because HeapTupleSatisfiesDirty will consider a tuple deleted
-			 * tuple deleted by our transaction dead, regardless of cmax.)
+			 * by our transaction dead, regardless of cmax.) Wee just checked
-			 * Wee just checked that priorXmax == xmin, so we can test that
+			 * that priorXmax == xmin, so we can test that variable instead of
-			 * variable instead of doing HeapTupleHeaderGetXmin again.
+			 * doing HeapTupleHeaderGetXmin again.
 			 */
 			if (TransactionIdIsCurrentTransactionId(priorXmax) &&
 				HeapTupleHeaderGetCmin(tuple.t_data) >= estate->es_output_cid)
@@ -1929,6 +1931,7 @@ EvalPlanQualFetch(EState *estate, Relation relation, int lockmode,
 			switch (test)
 			{
 				case HeapTupleSelfUpdated:
+
 					/*
 					 * The target tuple was already updated or deleted by the
 					 * current command, or by a later command in the current

src/backend/executor/nodeLockRows.c

@@ -139,6 +139,7 @@ lnext:
 		switch (test)
 		{
 			case HeapTupleSelfUpdated:
+
 				/*
 				 * The target tuple was already updated or deleted by the
 				 * current command, or by a later command in the current

src/backend/executor/nodeModifyTable.c

@@ -397,13 +397,14 @@ ldelete:;
 		switch (result)
 		{
 			case HeapTupleSelfUpdated:
+
 				/*
 				 * The target tuple was already updated or deleted by the
 				 * current command, or by a later command in the current
 				 * transaction.  The former case is possible in a join DELETE
-				 * where multiple tuples join to the same target tuple.
+				 * where multiple tuples join to the same target tuple. This
-				 * This is somewhat questionable, but Postgres has always
+				 * is somewhat questionable, but Postgres has always allowed
-				 * allowed it: we just ignore additional deletion attempts.
+				 * it: we just ignore additional deletion attempts.
 				 *
 				 * The latter case arises if the tuple is modified by a
 				 * command in a BEFORE trigger, or perhaps by a command in a
@@ -417,9 +418,9 @@ ldelete:;
 				 * to business rules; so throwing an error is the only safe
 				 * course.
 				 *
-				 * If a trigger actually intends this type of interaction,
+				 * If a trigger actually intends this type of interaction, it
-				 * it can re-execute the DELETE and then return NULL to
+				 * can re-execute the DELETE and then return NULL to cancel
-				 * cancel the outer delete.
+				 * the outer delete.
 				 */
 				if (hufd.cmax != estate->es_output_cid)
 					ereport(ERROR,
@@ -678,14 +679,15 @@ lreplace:;
 		switch (result)
 		{
 			case HeapTupleSelfUpdated:
+
 				/*
 				 * The target tuple was already updated or deleted by the
 				 * current command, or by a later command in the current
 				 * transaction.  The former case is possible in a join UPDATE
-				 * where multiple tuples join to the same target tuple.
+				 * where multiple tuples join to the same target tuple. This
-				 * This is pretty questionable, but Postgres has always
+				 * is pretty questionable, but Postgres has always allowed it:
-				 * allowed it: we just execute the first update action and
+				 * we just execute the first update action and ignore
-				 * ignore additional update attempts.
+				 * additional update attempts.
 				 *
 				 * The latter case arises if the tuple is modified by a
 				 * command in a BEFORE trigger, or perhaps by a command in a
@@ -697,9 +699,9 @@ lreplace:;
 				 * previous ones.  So throwing an error is the only safe
 				 * course.
 				 *
-				 * If a trigger actually intends this type of interaction,
+				 * If a trigger actually intends this type of interaction, it
-				 * it can re-execute the UPDATE (assuming it can figure out
+				 * can re-execute the UPDATE (assuming it can figure out how)
-				 * how) and then return NULL to cancel the outer update.
+				 * and then return NULL to cancel the outer update.
 				 */
 				if (hufd.cmax != estate->es_output_cid)
 					ereport(ERROR,

src/backend/optimizer/geqo/geqo_cx.c

@@ -47,7 +47,6 @@ int
 cx(PlannerInfo *root, Gene *tour1, Gene *tour2, Gene *offspring,
    int num_gene, City *city_table)
 {
-
 	int			i,
 				start_pos,
 				curr_pos;

src/backend/optimizer/geqo/geqo_px.c

@@ -46,7 +46,6 @@ void
 px(PlannerInfo *root, Gene *tour1, Gene *tour2, Gene *offspring, int num_gene,
    City *city_table)
 {
-
 	int			num_positions;
 	int			i,
 				pos,

src/backend/optimizer/path/equivclass.c

@@ -2083,9 +2083,9 @@ generate_implied_equalities_for_column(PlannerInfo *root,
 			continue;
 
 		/*
-		 * Scan members, looking for a match to the target column.  Note
+		 * Scan members, looking for a match to the target column.	Note that
-		 * that child EC members are considered, but only when they belong to
+		 * child EC members are considered, but only when they belong to the
-		 * the target relation.  (Unlike regular members, the same expression
+		 * target relation.  (Unlike regular members, the same expression
 		 * could be a child member of more than one EC.  Therefore, it's
 		 * potentially order-dependent which EC a child relation's target
 		 * column gets matched to.	This is annoying but it only happens in

src/backend/optimizer/path/indxpath.c

@@ -2630,8 +2630,8 @@ check_partial_indexes(PlannerInfo *root, RelOptInfo *rel)
 		return;
 
 	/*
-	 * Construct a list of clauses that we can assume true for the purpose
+	 * Construct a list of clauses that we can assume true for the purpose of
-	 * of proving the index(es) usable.  Restriction clauses for the rel are
+	 * proving the index(es) usable.  Restriction clauses for the rel are
 	 * always usable, and so are any join clauses that are "movable to" this
 	 * rel.  Also, we can consider any EC-derivable join clauses (which must
 	 * be "movable to" this rel, by definition).
@@ -2653,8 +2653,8 @@ check_partial_indexes(PlannerInfo *root, RelOptInfo *rel)
 	/*
 	 * Add on any equivalence-derivable join clauses.  Computing the correct
 	 * relid sets for generate_join_implied_equalities is slightly tricky
-	 * because the rel could be a child rel rather than a true baserel, and
+	 * because the rel could be a child rel rather than a true baserel, and in
-	 * in that case we must remove its parent's relid from all_baserels.
+	 * that case we must remove its parent's relid from all_baserels.
 	 */
 	if (rel->reloptkind == RELOPT_OTHER_MEMBER_REL)
 	{

src/backend/optimizer/plan/initsplan.c

@@ -861,11 +861,11 @@ make_outerjoininfo(PlannerInfo *root,
 	Assert(jointype != JOIN_RIGHT);
 
 	/*
-	 * Presently the executor cannot support FOR [KEY] UPDATE/SHARE marking of rels
+	 * Presently the executor cannot support FOR [KEY] UPDATE/SHARE marking of
-	 * appearing on the nullable side of an outer join. (It's somewhat unclear
+	 * rels appearing on the nullable side of an outer join. (It's somewhat
-	 * what that would mean, anyway: what should we mark when a result row is
+	 * unclear what that would mean, anyway: what should we mark when a result
-	 * generated from no element of the nullable relation?)  So, complain if
+	 * row is generated from no element of the nullable relation?)	So,
-	 * any nullable rel is FOR [KEY] UPDATE/SHARE.
+	 * complain if any nullable rel is FOR [KEY] UPDATE/SHARE.
 	 *
 	 * You might be wondering why this test isn't made far upstream in the
 	 * parser.	It's because the parser hasn't got enough info --- consider

src/backend/optimizer/plan/planagg.c

@@ -260,8 +260,8 @@ optimize_minmax_aggregates(PlannerInfo *root, List *tlist,
 	 * We have to replace Aggrefs with Params in equivalence classes too, else
 	 * ORDER BY or DISTINCT on an optimized aggregate will fail.  We don't
 	 * need to process child eclass members though, since they aren't of
-	 * interest anymore --- and replace_aggs_with_params_mutator isn't able
+	 * interest anymore --- and replace_aggs_with_params_mutator isn't able to
-	 * to handle Aggrefs containing translated child Vars, anyway.
+	 * handle Aggrefs containing translated child Vars, anyway.
 	 *
 	 * Note: at some point it might become necessary to mutate other data
 	 * structures too, such as the query's sortClause or distinctClause. Right

src/backend/optimizer/plan/planner.c

@@ -571,9 +571,9 @@ subquery_planner(PlannerGlobal *glob, Query *parse,
 				returningLists = NIL;
 
 			/*
-			 * If there was a FOR [KEY] UPDATE/SHARE clause, the LockRows node will
+			 * If there was a FOR [KEY] UPDATE/SHARE clause, the LockRows node
-			 * have dealt with fetching non-locked marked rows, else we need
+			 * will have dealt with fetching non-locked marked rows, else we
-			 * to have ModifyTable do that.
+			 * need to have ModifyTable do that.
 			 */
 			if (parse->rowMarks)
 				rowMarks = NIL;
@@ -964,8 +964,8 @@ inheritance_planner(PlannerInfo *root)
 	root->simple_rel_array = save_rel_array;
 
 	/*
-	 * If there was a FOR [KEY] UPDATE/SHARE clause, the LockRows node will have
+	 * If there was a FOR [KEY] UPDATE/SHARE clause, the LockRows node will
-	 * dealt with fetching non-locked marked rows, else we need to have
+	 * have dealt with fetching non-locked marked rows, else we need to have
 	 * ModifyTable do that.
 	 */
 	if (parse->rowMarks)
@@ -1075,8 +1075,8 @@ grouping_planner(PlannerInfo *root, double tuple_fraction)
 										tlist);
 
 		/*
-		 * Can't handle FOR [KEY] UPDATE/SHARE here (parser should have checked
+		 * Can't handle FOR [KEY] UPDATE/SHARE here (parser should have
-		 * already, but let's make sure).
+		 * checked already, but let's make sure).
 		 */
 		if (parse->rowMarks)
 			ereport(ERROR,
@@ -1741,9 +1741,9 @@ grouping_planner(PlannerInfo *root, double tuple_fraction)
 	}
 
 	/*
-	 * If there is a FOR [KEY] UPDATE/SHARE clause, add the LockRows node. (Note: we
+	 * If there is a FOR [KEY] UPDATE/SHARE clause, add the LockRows node.
-	 * intentionally test parse->rowMarks not root->rowMarks here. If there
+	 * (Note: we intentionally test parse->rowMarks not root->rowMarks here.
-	 * are only non-locking rowmarks, they should be handled by the
+	 * If there are only non-locking rowmarks, they should be handled by the
 	 * ModifyTable node instead.)
 	 */
 	if (parse->rowMarks)
@@ -1927,9 +1927,9 @@ preprocess_rowmarks(PlannerInfo *root)
 	if (parse->rowMarks)
 	{
 		/*
-		 * We've got trouble if FOR [KEY] UPDATE/SHARE appears inside grouping,
+		 * We've got trouble if FOR [KEY] UPDATE/SHARE appears inside
-		 * since grouping renders a reference to individual tuple CTIDs
+		 * grouping, since grouping renders a reference to individual tuple
-		 * invalid.  This is also checked at parse time, but that's
+		 * CTIDs invalid.  This is also checked at parse time, but that's
 		 * insufficient because of rule substitution, query pullup, etc.
 		 */
 		CheckSelectLocking(parse);
@@ -1937,7 +1937,8 @@ preprocess_rowmarks(PlannerInfo *root)
 	else
 	{
 		/*
-		 * We only need rowmarks for UPDATE, DELETE, or FOR [KEY] UPDATE/SHARE.
+		 * We only need rowmarks for UPDATE, DELETE, or FOR [KEY]
+		 * UPDATE/SHARE.
 		 */
 		if (parse->commandType != CMD_UPDATE &&
 			parse->commandType != CMD_DELETE)

src/backend/optimizer/prep/prepjointree.c

@@ -1288,9 +1288,9 @@ is_simple_subquery(Query *subquery, RangeTblEntry *rte,
 		return false;
 
 	/*
-	 * Don't pull up if the RTE represents a security-barrier view; we couldn't
+	 * Don't pull up if the RTE represents a security-barrier view; we
-	 * prevent information leakage once the RTE's Vars are scattered about in
+	 * couldn't prevent information leakage once the RTE's Vars are scattered
-	 * the upper query.
+	 * about in the upper query.
 	 */
 	if (rte->security_barrier)
 		return false;

src/backend/optimizer/util/pathnode.c

@@ -282,6 +282,7 @@ set_cheapest(RelOptInfo *parent_rel)
 						/* old path is less-parameterized, keep it */
 						break;
 					case BMS_DIFFERENT:
+
 						/*
 						 * This means that neither path has the least possible
 						 * parameterization for the rel.  We'll sit on the old
@@ -328,8 +329,8 @@ set_cheapest(RelOptInfo *parent_rel)
 		parameterized_paths = lcons(cheapest_total_path, parameterized_paths);
 
 	/*
-	 * If there is no unparameterized path, use the best parameterized path
+	 * If there is no unparameterized path, use the best parameterized path as
-	 * as cheapest_total_path (but not as cheapest_startup_path).
+	 * cheapest_total_path (but not as cheapest_startup_path).
 	 */
 	if (cheapest_total_path == NULL)
 		cheapest_total_path = best_param_path;

src/backend/parser/analyze.c

@@ -2167,10 +2167,10 @@ transformCreateTableAsStmt(ParseState *pstate, CreateTableAsStmt *stmt)
 					 errmsg("materialized views may not be defined using bound parameters")));
 
 		/*
-		 * For now, we disallow unlogged materialized views, because it
+		 * For now, we disallow unlogged materialized views, because it seems
-		 * seems like a bad idea for them to just go to empty after a crash.
+		 * like a bad idea for them to just go to empty after a crash. (If we
-		 * (If we could mark them as unpopulated, that would be better, but
+		 * could mark them as unpopulated, that would be better, but that
-		 * that requires catalog changes which crash recovery can't presently
+		 * requires catalog changes which crash recovery can't presently
 		 * handle.)
 		 */
 		if (stmt->into->rel->relpersistence == RELPERSISTENCE_UNLOGGED)
@@ -2394,8 +2394,8 @@ applyLockingClause(Query *qry, Index rtindex,
 	{
 		/*
 		 * If the same RTE is specified for more than one locking strength,
-		 * treat is as the strongest.  (Reasonable, since you can't take both a
+		 * treat is as the strongest.  (Reasonable, since you can't take both
-		 * shared and exclusive lock at the same time; it'll end up being
+		 * a shared and exclusive lock at the same time; it'll end up being
 		 * exclusive anyway.)
 		 *
 		 * We also consider that NOWAIT wins if it's specified both ways. This

src/backend/parser/check_keywords.pl

@@ -52,6 +52,7 @@ line: while (<GRAM>)
 
 	if (!($kcat))
 	{
+
 		# Is this the beginning of a keyword list?
 		foreach $k (keys %keyword_categories)
 		{
@@ -81,6 +82,7 @@ line: while (<GRAM>)
 		}
 		elsif ($arr[$fieldIndexer] eq '/*')
 		{
+
 			# start of a multiline comment
 			$comment = 1;
 			next;
@@ -92,6 +94,7 @@ line: while (<GRAM>)
 
 		if ($arr[$fieldIndexer] eq ';')
 		{
+
 			# end of keyword list
 			$kcat = '';
 			next;
@@ -116,6 +119,7 @@ foreach $kcat (keys %keyword_categories)
 
 	foreach $kword (@{ $keywords{$kcat} })
 	{
+
 		# Some keyword have a _P suffix. Remove it for the comparison.
 		$bare_kword = $kword;
 		$bare_kword =~ s/_P$//;
@@ -206,6 +210,7 @@ kwlist_line: while (<KWLIST>)
 			}
 			else
 			{
+
 				# Remove it from the hash, so that we can
 				# complain at the end if there's keywords left
 				# that were not found in kwlist.h

src/backend/parser/parse_clause.c

@@ -715,8 +715,8 @@ transformFromClauseItem(ParseState *pstate, Node *n,
 		/*
 		 * Make the left-side RTEs available for LATERAL access within the
 		 * right side, by temporarily adding them to the pstate's namespace
-		 * list.  Per SQL:2008, if the join type is not INNER or LEFT then
+		 * list.  Per SQL:2008, if the join type is not INNER or LEFT then the
-		 * the left-side names must still be exposed, but it's an error to
+		 * left-side names must still be exposed, but it's an error to
 		 * reference them.	(Stupid design, but that's what it says.)  Hence,
 		 * we always push them into the namespace, but mark them as not
 		 * lateral_ok if the jointype is wrong.

src/backend/parser/parse_expr.c

@@ -1411,9 +1411,9 @@ transformSubLink(ParseState *pstate, SubLink *sublink)
 		return result;
 
 	/*
-	 * Check to see if the sublink is in an invalid place within the query.
+	 * Check to see if the sublink is in an invalid place within the query. We
-	 * We allow sublinks everywhere in SELECT/INSERT/UPDATE/DELETE, but
+	 * allow sublinks everywhere in SELECT/INSERT/UPDATE/DELETE, but generally
-	 * generally not in utility statements.
+	 * not in utility statements.
 	 */
 	err = NULL;
 	switch (pstate->p_expr_kind)

src/backend/parser/parse_utilcmd.c

@@ -556,6 +556,7 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column)
 					errmsg("constraints are not supported on foreign tables"),
 							 parser_errposition(cxt->pstate,
 												constraint->location)));
+
 				/*
 				 * Fill in the current attribute's name and throw it into the
 				 * list of FK constraints to be processed later.
@@ -1405,8 +1406,8 @@ transformIndexConstraints(CreateStmtContext *cxt)
 	/*
 	 * Scan the index list and remove any redundant index specifications. This
 	 * can happen if, for instance, the user writes UNIQUE PRIMARY KEY. A
-	 * strict reading of SQL would suggest raising an error instead, but
+	 * strict reading of SQL would suggest raising an error instead, but that
-	 * that strikes me as too anal-retentive. - tgl 2001-02-14
+	 * strikes me as too anal-retentive. - tgl 2001-02-14
 	 *
 	 * XXX in ALTER TABLE case, it'd be nice to look for duplicate
 	 * pre-existing indexes, too.

src/backend/port/sysv_shmem.c

@@ -384,10 +384,10 @@ PGSharedMemoryCreate(Size size, bool makePrivate, int port)
 	 * settings.
 	 *
 	 * However, we disable this logic in the EXEC_BACKEND case, and fall back
-	 * to the old method of allocating the entire segment using System V shared
+	 * to the old method of allocating the entire segment using System V
-	 * memory, because there's no way to attach an mmap'd segment to a process
+	 * shared memory, because there's no way to attach an mmap'd segment to a
-	 * after exec().  Since EXEC_BACKEND is intended only for developer use,
+	 * process after exec().  Since EXEC_BACKEND is intended only for
-	 * this shouldn't be a big problem.
+	 * developer use, this shouldn't be a big problem.
 	 */
 #ifndef EXEC_BACKEND
 	{
@@ -406,9 +406,9 @@ PGSharedMemoryCreate(Size size, bool makePrivate, int port)
 		/*
 		 * We assume that no one will attempt to run PostgreSQL 9.3 or later
 		 * on systems that are ancient enough that anonymous shared memory is
-		 * not supported, such as pre-2.4 versions of Linux.  If that turns out
+		 * not supported, such as pre-2.4 versions of Linux.  If that turns
-		 * to be false, we might need to add a run-time test here and do this
+		 * out to be false, we might need to add a run-time test here and do
-		 * only if the running kernel supports it.
+		 * this only if the running kernel supports it.
 		 */
 		AnonymousShmem = mmap(NULL, size, PROT_READ | PROT_WRITE, PG_MMAP_FLAGS,
 							  -1, 0);
@@ -519,9 +519,9 @@ PGSharedMemoryCreate(Size size, bool makePrivate, int port)
 
 	/*
 	 * If AnonymousShmem is NULL here, then we're not using anonymous shared
-	 * memory, and should return a pointer to the System V shared memory block.
+	 * memory, and should return a pointer to the System V shared memory
-	 * Otherwise, the System V shared memory block is only a shim, and we must
+	 * block. Otherwise, the System V shared memory block is only a shim, and
-	 * return a pointer to the real block.
+	 * we must return a pointer to the real block.
 	 */
 	if (AnonymousShmem == NULL)
 		return hdr;

src/backend/postmaster/autovacuum.c

@@ -949,8 +949,8 @@ rebuild_database_list(Oid newdb)
 		PgStat_StatDBEntry *entry;
 
 		/*
-		 * skip databases with no stat entries -- in particular, this gets
+		 * skip databases with no stat entries -- in particular, this gets rid
-		 * rid of dropped databases
+		 * of dropped databases
 		 */
 		entry = pgstat_fetch_stat_dbentry(avdb->adl_datid);
 		if (entry == NULL)

src/backend/postmaster/checkpointer.c

@@ -930,8 +930,8 @@ CheckpointerShmemInit(void)
 	{
 		/*
 		 * First time through, so initialize.  Note that we zero the whole
-		 * requests array; this is so that CompactCheckpointerRequestQueue
+		 * requests array; this is so that CompactCheckpointerRequestQueue can
-		 * can assume that any pad bytes in the request structs are zeroes.
+		 * assume that any pad bytes in the request structs are zeroes.
 		 */
 		MemSet(CheckpointerShmem, 0, size);
 		SpinLockInit(&CheckpointerShmem->ckpt_lck);

src/backend/postmaster/fork_process.c

@@ -102,9 +102,9 @@ fork_process(void)
 
 		/*
 		 * Older Linux kernels have oom_adj not oom_score_adj.	This works
-		 * similarly except with a different scale of adjustment values.
+		 * similarly except with a different scale of adjustment values. If
-		 * If it's necessary to build Postgres to work with either API,
+		 * it's necessary to build Postgres to work with either API, you can
-		 * you can define both LINUX_OOM_SCORE_ADJ and LINUX_OOM_ADJ.
+		 * define both LINUX_OOM_SCORE_ADJ and LINUX_OOM_ADJ.
 		 */
 #ifdef LINUX_OOM_ADJ
 		{

src/backend/postmaster/pgstat.c

@@ -4401,9 +4401,9 @@ pgstat_recv_inquiry(PgStat_MsgInquiry *msg, int len)
 	 * request's cutoff time, update it; otherwise there's nothing to do.
 	 *
 	 * Note that if a request is found, we return early and skip the below
-	 * check for clock skew.  This is okay, since the only way for a DB request
+	 * check for clock skew.  This is okay, since the only way for a DB
-	 * to be present in the list is that we have been here since the last write
+	 * request to be present in the list is that we have been here since the
-	 * round.
+	 * last write round.
 	 */
 	slist_foreach(iter, &last_statrequests)
 	{

src/backend/postmaster/postmaster.c

@@ -207,8 +207,10 @@ BackgroundWorker *MyBgworkerEntry = NULL;
 
 /* The socket number we are listening for connections on */
 int			PostPortNumber;
+
 /* The directory names for Unix socket(s) */
 char	   *Unix_socket_directories;
+
 /* The TCP listen address(es) */
 char	   *ListenAddresses;
 
@@ -1212,8 +1214,8 @@ PostmasterMain(int argc, char *argv[])
 		/*
 		 * We can start up without the IDENT file, although it means that you
 		 * cannot log in using any of the authentication methods that need a
-		 * user name mapping. load_ident() already logged the details of
+		 * user name mapping. load_ident() already logged the details of error
-		 * error to the log.
+		 * to the log.
 		 */
 	}
 
@@ -5214,11 +5216,11 @@ RegisterBackgroundWorker(BackgroundWorker *worker)
 	}
 
 	/*
-	 * Enforce maximum number of workers.  Note this is overly restrictive:
+	 * Enforce maximum number of workers.  Note this is overly restrictive: we
-	 * we could allow more non-shmem-connected workers, because these don't
+	 * could allow more non-shmem-connected workers, because these don't count
-	 * count towards the MAX_BACKENDS limit elsewhere.  This doesn't really
+	 * towards the MAX_BACKENDS limit elsewhere.  This doesn't really matter
-	 * matter for practical purposes; several million processes would need to
+	 * for practical purposes; several million processes would need to run on
-	 * run on a single server.
+	 * a single server.
 	 */
 	if (++numworkers > maxworkers)
 	{

src/backend/postmaster/syslogger.c

@@ -583,8 +583,8 @@ SysLogger_Start(void)
 
 	/*
 	 * The initial logfile is created right in the postmaster, to verify that
-	 * the Log_directory is writable.  We save the reference time so that
+	 * the Log_directory is writable.  We save the reference time so that the
-	 * the syslogger child process can recompute this file name.
+	 * syslogger child process can recompute this file name.
 	 *
 	 * It might look a bit strange to re-do this during a syslogger restart,
 	 * but we must do so since the postmaster closed syslogFile after the

src/backend/regex/regprefix.c

@@ -79,8 +79,8 @@ pg_regprefix(regex_t *re,
 
 	/*
 	 * Since a correct NFA should never contain any exit-free loops, it should
-	 * not be possible for our traversal to return to a previously visited
+	 * not be possible for our traversal to return to a previously visited NFA
-	 * NFA state.  Hence we need at most nstates chrs in the output string.
+	 * state.  Hence we need at most nstates chrs in the output string.
 	 */
 	*string = (chr *) MALLOC(cnfa->nstates * sizeof(chr));
 	if (*string == NULL)
@@ -122,8 +122,8 @@ findprefix(struct cnfa * cnfa,
 
 	/*
 	 * The "pre" state must have only BOS/BOL outarcs, else pattern isn't
-	 * anchored left.  If we have both BOS and BOL, they must go to the
+	 * anchored left.  If we have both BOS and BOL, they must go to the same
-	 * same next state.
+	 * next state.
 	 */
 	st = cnfa->pre;
 	nextst = -1;

src/backend/replication/basebackup.c

@@ -249,8 +249,8 @@ perform_base_backup(basebackup_options *opt, DIR *tblspcdir)
 		 * I'd rather not worry about timelines here, so scan pg_xlog and
 		 * include all WAL files in the range between 'startptr' and 'endptr',
 		 * regardless of the timeline the file is stamped with. If there are
-		 * some spurious WAL files belonging to timelines that don't belong
+		 * some spurious WAL files belonging to timelines that don't belong in
-		 * in this server's history, they will be included too. Normally there
+		 * this server's history, they will be included too. Normally there
 		 * shouldn't be such files, but if there are, there's little harm in
 		 * including them.
 		 */
@@ -290,9 +290,9 @@ perform_base_backup(basebackup_options *opt, DIR *tblspcdir)
 		CheckXLogRemoved(startsegno, ThisTimeLineID);
 
 		/*
-		 * Put the WAL filenames into an array, and sort. We send the files
+		 * Put the WAL filenames into an array, and sort. We send the files in
-		 * in order from oldest to newest, to reduce the chance that a file
+		 * order from oldest to newest, to reduce the chance that a file is
-		 * is recycled before we get a chance to send it over.
+		 * recycled before we get a chance to send it over.
 		 */
 		nWalFiles = list_length(walFileList);
 		walFiles = palloc(nWalFiles * sizeof(char *));
@@ -311,6 +311,7 @@ perform_base_backup(basebackup_options *opt, DIR *tblspcdir)
 		if (segno != startsegno)
 		{
 			char		startfname[MAXFNAMELEN];
+
 			XLogFileName(startfname, ThisTimeLineID, startsegno);
 			ereport(ERROR,
 					(errmsg("could not find WAL file \"%s\"", startfname)));
@@ -324,6 +325,7 @@ perform_base_backup(basebackup_options *opt, DIR *tblspcdir)
 			if (!(nextsegno == segno || currsegno == segno))
 			{
 				char		nextfname[MAXFNAMELEN];
+
 				XLogFileName(nextfname, ThisTimeLineID, nextsegno);
 				ereport(ERROR,
 					  (errmsg("could not find WAL file \"%s\"", nextfname)));
@@ -332,6 +334,7 @@ perform_base_backup(basebackup_options *opt, DIR *tblspcdir)
 		if (segno != endsegno)
 		{
 			char		endfname[MAXFNAMELEN];
+
 			XLogFileName(endfname, ThisTimeLineID, endsegno);
 			ereport(ERROR,
 					(errmsg("could not find WAL file \"%s\"", endfname)));
@@ -415,6 +418,7 @@ perform_base_backup(basebackup_options *opt, DIR *tblspcdir)
 		foreach(lc, historyFileList)
 		{
 			char	   *fname = lfirst(lc);
+
 			snprintf(pathbuf, MAXPGPATH, XLOGDIR "/%s", fname);
 
 			if (lstat(pathbuf, &statbuf) != 0)
@@ -657,6 +661,7 @@ SendXlogRecPtrResult(XLogRecPtr ptr, TimeLineID tli)
 	pq_sendstring(&buf, "tli");
 	pq_sendint(&buf, 0, 4);		/* table oid */
 	pq_sendint(&buf, 0, 2);		/* attnum */
+
 	/*
 	 * int8 may seem like a surprising data type for this, but in thory int4
 	 * would not be wide enough for this, as TimeLineID is unsigned.
@@ -747,7 +752,8 @@ sendTablespace(char *path, bool sizeonly)
 			 TABLESPACE_VERSION_DIRECTORY);
 
 	/*
-	 * Store a directory entry in the tar file so we get the permissions right.
+	 * Store a directory entry in the tar file so we get the permissions
+	 * right.
 	 */
 	if (lstat(pathbuf, &statbuf) != 0)
 	{

src/backend/replication/libpqwalreceiver/libpqwalreceiver.c

@@ -214,7 +214,8 @@ libpqrcv_endstreaming(TimeLineID *next_tli)
 
 	/*
 	 * After COPY is finished, we should receive a result set indicating the
-	 * next timeline's ID, or just CommandComplete if the server was shut down.
+	 * next timeline's ID, or just CommandComplete if the server was shut
+	 * down.
 	 *
 	 * If we had not yet received CopyDone from the backend, PGRES_COPY_IN
 	 * would also be possible. However, at the moment this function is only

src/backend/replication/walreceiver.c

@@ -332,12 +332,13 @@ WalReceiverMain(void)
 
 		/*
 		 * Get any missing history files. We do this always, even when we're
-		 * not interested in that timeline, so that if we're promoted to become
+		 * not interested in that timeline, so that if we're promoted to
-		 * the master later on, we don't select the same timeline that was
+		 * become the master later on, we don't select the same timeline that
-		 * already used in the current master. This isn't bullet-proof - you'll
+		 * was already used in the current master. This isn't bullet-proof -
-		 * need some external software to manage your cluster if you need to
+		 * you'll need some external software to manage your cluster if you
-		 * ensure that a unique timeline id is chosen in every case, but let's
+		 * need to ensure that a unique timeline id is chosen in every case,
-		 * avoid the confusion of timeline id collisions where we can.
+		 * but let's avoid the confusion of timeline id collisions where we
+		 * can.
 		 */
 		WalRcvFetchTimeLineHistoryFiles(startpointTLI, primaryTLI);
 
@@ -387,7 +388,8 @@ WalReceiverMain(void)
 
 				/*
 				 * Emergency bailout if postmaster has died.  This is to avoid
-				 * the necessity for manual cleanup of all postmaster children.
+				 * the necessity for manual cleanup of all postmaster
+				 * children.
 				 */
 				if (!PostmasterIsAlive())
 					exit(1);
@@ -422,7 +424,10 @@ WalReceiverMain(void)
 					{
 						if (len > 0)
 						{
-							/* Something was received from master, so reset timeout */
+							/*
+							 * Something was received from master, so reset
+							 * timeout
+							 */
 							last_recv_timestamp = GetCurrentTimestamp();
 							ping_sent = false;
 							XLogWalRcvProcessMsg(buf[0], &buf[1], len - 1);
@@ -457,10 +462,11 @@ WalReceiverMain(void)
 					/*
 					 * We didn't receive anything new. If we haven't heard
 					 * anything from the server for more than
-					 * wal_receiver_timeout / 2, ping the server. Also, if it's
+					 * wal_receiver_timeout / 2, ping the server. Also, if
-					 * been longer than wal_receiver_status_interval since the
+					 * it's been longer than wal_receiver_status_interval
-					 * last update we sent, send a status update to the master
+					 * since the last update we sent, send a status update to
-					 * anyway, to report any progress in applying WAL.
+					 * the master anyway, to report any progress in applying
+					 * WAL.
 					 */
 					bool		requestReply = false;
 
@@ -482,8 +488,8 @@ WalReceiverMain(void)
 									(errmsg("terminating walreceiver due to timeout")));
 
 						/*
-						 * We didn't receive anything new, for half of receiver
+						 * We didn't receive anything new, for half of
-						 * replication timeout. Ping the server.
+						 * receiver replication timeout. Ping the server.
 						 */
 						if (!ping_sent)
 						{
@@ -511,9 +517,9 @@ WalReceiverMain(void)
 			DisableWalRcvImmediateExit();
 
 			/*
-			 * If the server had switched to a new timeline that we didn't know
+			 * If the server had switched to a new timeline that we didn't
-			 * about when we began streaming, fetch its timeline history file
+			 * know about when we began streaming, fetch its timeline history
-			 * now.
+			 * file now.
 			 */
 			WalRcvFetchTimeLineHistoryFiles(startpointTLI, primaryTLI);
 		}
@@ -614,8 +620,8 @@ WalRcvWaitForStartPosition(XLogRecPtr *startpoint, TimeLineID *startpointTLI)
 		if (walrcv->walRcvState == WALRCV_STOPPING)
 		{
 			/*
-			 * We should've received SIGTERM if the startup process wants
+			 * We should've received SIGTERM if the startup process wants us
-			 * us to die, but might as well check it here too.
+			 * to die, but might as well check it here too.
 			 */
 			SpinLockRelease(&walrcv->mutex);
 			exit(1);
@@ -664,8 +670,9 @@ WalRcvFetchTimeLineHistoryFiles(TimeLineID first, TimeLineID last)
 			DisableWalRcvImmediateExit();
 
 			/*
-			 * Check that the filename on the master matches what we calculated
+			 * Check that the filename on the master matches what we
-			 * ourselves. This is just a sanity check, it should always match.
+			 * calculated ourselves. This is just a sanity check, it should
+			 * always match.
 			 */
 			TLHistoryFileName(expectedfname, tli);
 			if (strcmp(fname, expectedfname) != 0)
@@ -890,8 +897,8 @@ XLogWalRcvWrite(char *buf, Size nbytes, XLogRecPtr recptr)
 									XLogFileNameP(recvFileTLI, recvSegNo))));
 
 				/*
-				 * Create .done file forcibly to prevent the streamed segment from
+				 * Create .done file forcibly to prevent the streamed segment
-				 * being archived later.
+				 * from being archived later.
 				 */
 				XLogFileName(xlogfname, recvFileTLI, recvSegNo);
 				XLogArchiveForceDone(xlogfname);

src/backend/replication/walsender.c

@@ -96,6 +96,7 @@ bool		am_cascading_walsender = false;		/* Am I cascading WAL to
 int			max_wal_senders = 0;	/* the maximum number of concurrent walsenders */
 int			wal_sender_timeout = 60 * 1000;		/* maximum time to send one
 												 * WAL data message */
+
 /*
  * State for WalSndWakeupRequest
  */
@@ -138,6 +139,7 @@ static StringInfoData tmpbuf;
  * Timestamp of the last receipt of the reply from the standby.
  */
 static TimestampTz last_reply_timestamp;
+
 /* Have we sent a heartbeat message asking for reply, since last reply? */
 static bool ping_sent = false;
 
@@ -322,8 +324,8 @@ SendTimeLineHistory(TimeLineHistoryCmd *cmd)
 	off_t		bytesleft;
 
 	/*
-	 * Reply with a result set with one row, and two columns. The first col
+	 * Reply with a result set with one row, and two columns. The first col is
-	 * is the name of the history file, 2nd is the contents.
+	 * the name of the history file, 2nd is the contents.
 	 */
 
 	TLHistoryFileName(histfname, cmd->timeline);
@@ -420,8 +422,8 @@ StartReplication(StartReplicationCmd *cmd)
 
 	/*
 	 * Select the timeline. If it was given explicitly by the client, use
-	 * that. Otherwise use the timeline of the last replayed record, which
+	 * that. Otherwise use the timeline of the last replayed record, which is
-	 * is kept in ThisTimeLineID.
+	 * kept in ThisTimeLineID.
 	 */
 	if (am_cascading_walsender)
 	{
@@ -448,8 +450,8 @@ StartReplication(StartReplicationCmd *cmd)
 			sendTimeLineIsHistoric = true;
 
 			/*
-			 * Check that the timeline the client requested for exists, and the
+			 * Check that the timeline the client requested for exists, and
-			 * requested start location is on that timeline.
+			 * the requested start location is on that timeline.
 			 */
 			timeLineHistory = readTimeLineHistory(ThisTimeLineID);
 			switchpoint = tliSwitchPoint(cmd->timeline, timeLineHistory,
@@ -461,14 +463,14 @@ StartReplication(StartReplicationCmd *cmd)
 			 * requested startpoint is on that timeline in our history.
 			 *
 			 * This is quite loose on purpose. We only check that we didn't
-			 * fork off the requested timeline before the switchpoint. We don't
+			 * fork off the requested timeline before the switchpoint. We
-			 * check that we switched *to* it before the requested starting
+			 * don't check that we switched *to* it before the requested
-			 * point. This is because the client can legitimately request to
+			 * starting point. This is because the client can legitimately
-			 * start replication from the beginning of the WAL segment that
+			 * request to start replication from the beginning of the WAL
-			 * contains switchpoint, but on the new timeline, so that it
+			 * segment that contains switchpoint, but on the new timeline, so
-			 * doesn't end up with a partial segment. If you ask for a too old
+			 * that it doesn't end up with a partial segment. If you ask for a
-			 * starting point, you'll get an error later when we fail to find
+			 * too old starting point, you'll get an error later when we fail
-			 * the requested WAL segment in pg_xlog.
+			 * to find the requested WAL segment in pg_xlog.
 			 *
 			 * XXX: we could be more strict here and only allow a startpoint
 			 * that's older than the switchpoint, if it it's still in the same
@@ -503,12 +505,13 @@ StartReplication(StartReplicationCmd *cmd)
 	if (!sendTimeLineIsHistoric || cmd->startpoint < sendTimeLineValidUpto)
 	{
 		/*
-		 * When we first start replication the standby will be behind the primary.
+		 * When we first start replication the standby will be behind the
-		 * For some applications, for example, synchronous replication, it is
+		 * primary. For some applications, for example, synchronous
-		 * important to have a clear state for this initial catchup mode, so we
+		 * replication, it is important to have a clear state for this initial
-		 * can trigger actions when we change streaming state later. We may stay
+		 * catchup mode, so we can trigger actions when we change streaming
-		 * in this state for a long time, which is exactly why we want to be able
+		 * state later. We may stay in this state for a long time, which is
-		 * to monitor whether or not we are still here.
+		 * exactly why we want to be able to monitor whether or not we are
+		 * still here.
 		 */
 		WalSndSetState(WALSNDSTATE_CATCHUP);
 
@@ -582,6 +585,7 @@ StartReplication(StartReplicationCmd *cmd)
 		pq_sendstring(&buf, "next_tli");
 		pq_sendint(&buf, 0, 4); /* table oid */
 		pq_sendint(&buf, 0, 2); /* attnum */
+
 		/*
 		 * int8 may seem like a surprising data type for this, but in theory
 		 * int4 would not be wide enough for this, as TimeLineID is unsigned.
@@ -932,11 +936,11 @@ ProcessStandbyHSFeedbackMessage(void)
 	 * cleanup conflicts on the standby server.
 	 *
 	 * There is a small window for a race condition here: although we just
-	 * checked that feedbackXmin precedes nextXid, the nextXid could have gotten
+	 * checked that feedbackXmin precedes nextXid, the nextXid could have
-	 * advanced between our fetching it and applying the xmin below, perhaps
+	 * gotten advanced between our fetching it and applying the xmin below,
-	 * far enough to make feedbackXmin wrap around.  In that case the xmin we
+	 * perhaps far enough to make feedbackXmin wrap around.  In that case the
-	 * set here would be "in the future" and have no effect.  No point in
+	 * xmin we set here would be "in the future" and have no effect.  No point
-	 * worrying about this since it's too late to save the desired data
+	 * in worrying about this since it's too late to save the desired data
 	 * anyway.	Assuming that the standby sends us an increasing sequence of
 	 * xmins, this could only happen during the first reply cycle, else our
 	 * own xmin would prevent nextXid from advancing so far.
@@ -969,8 +973,8 @@ WalSndLoop(void)
 	ping_sent = false;
 
 	/*
-	 * Loop until we reach the end of this timeline or the client requests
+	 * Loop until we reach the end of this timeline or the client requests to
-	 * to stop streaming.
+	 * stop streaming.
 	 */
 	for (;;)
 	{
@@ -1082,8 +1086,8 @@ WalSndLoop(void)
 			{
 				/*
 				 * If half of wal_sender_timeout has lapsed without receiving
-				 * any reply from standby, send a keep-alive message to standby
+				 * any reply from standby, send a keep-alive message to
-				 * requesting an immediate reply.
+				 * standby requesting an immediate reply.
 				 */
 				timeout = TimestampTzPlusMilliseconds(last_reply_timestamp,
 													  wal_sender_timeout / 2);
@@ -1133,6 +1137,7 @@ WalSndLoop(void)
 	return;
 
 send_failure:
+
 	/*
 	 * Get here on send failure.  Clean up and exit.
 	 *
@@ -1431,16 +1436,16 @@ XLogSend(bool *caughtup)
 		/*
 		 * Streaming the latest timeline on a standby.
 		 *
-		 * Attempt to send all WAL that has already been replayed, so that
+		 * Attempt to send all WAL that has already been replayed, so that we
-		 * we know it's valid. If we're receiving WAL through streaming
+		 * know it's valid. If we're receiving WAL through streaming
 		 * replication, it's also OK to send any WAL that has been received
 		 * but not replayed.
 		 *
 		 * The timeline we're recovering from can change, or we can be
-		 * promoted. In either case, the current timeline becomes historic.
+		 * promoted. In either case, the current timeline becomes historic. We
-		 * We need to detect that so that we don't try to stream past the
+		 * need to detect that so that we don't try to stream past the point
-		 * point where we switched to another timeline. We check for promotion
+		 * where we switched to another timeline. We check for promotion or
-		 * or timeline switch after calculating FlushPtr, to avoid a race
+		 * timeline switch after calculating FlushPtr, to avoid a race
 		 * condition: if the timeline becomes historic just after we checked
 		 * that it was still current, it's still be OK to stream it up to the
 		 * FlushPtr that was calculated before it became historic.
@@ -1509,13 +1514,14 @@ XLogSend(bool *caughtup)
 	 * forked to the next timeline, stop streaming.
 	 *
 	 * Note: We might already have sent WAL > sendTimeLineValidUpto. The
-	 * startup process will normally replay all WAL that has been received from
+	 * startup process will normally replay all WAL that has been received
-	 * the master, before promoting, but if the WAL streaming is terminated at
+	 * from the master, before promoting, but if the WAL streaming is
-	 * a WAL page boundary, the valid portion of the timeline might end in the
+	 * terminated at a WAL page boundary, the valid portion of the timeline
-	 * middle of a WAL record. We might've already sent the first half of that
+	 * might end in the middle of a WAL record. We might've already sent the
-	 * partial WAL record to the cascading standby, so that sentPtr >
+	 * first half of that partial WAL record to the cascading standby, so that
-	 * sendTimeLineValidUpto. That's OK; the cascading standby can't replay the
+	 * sentPtr > sendTimeLineValidUpto. That's OK; the cascading standby can't
-	 * partial WAL record either, so it can still follow our timeline switch.
+	 * replay the partial WAL record either, so it can still follow our
+	 * timeline switch.
 	 */
 	if (sendTimeLineIsHistoric && sendTimeLineValidUpto <= sentPtr)
 	{
@@ -1651,8 +1657,8 @@ GetStandbyFlushRecPtr(void)
 
 	/*
 	 * We can safely send what's already been replayed. Also, if walreceiver
-	 * is streaming WAL from the same timeline, we can send anything that
+	 * is streaming WAL from the same timeline, we can send anything that it
-	 * it has streamed, but hasn't been replayed yet.
+	 * has streamed, but hasn't been replayed yet.
 	 */
 
 	receivePtr = GetWalRcvWriteRecPtr(NULL, &receiveTLI);

src/backend/rewrite/rewriteDefine.c

@@ -541,9 +541,9 @@ DefineQueryRewrite(char *rulename,
 		DeleteSystemAttributeTuples(event_relid);
 
 		/*
-		 * Drop the toast table if any.  (This won't take care of updating
+		 * Drop the toast table if any.  (This won't take care of updating the
-		 * the toast fields in the relation's own pg_class entry; we handle
+		 * toast fields in the relation's own pg_class entry; we handle that
-		 * that below.)
+		 * below.)
 		 */
 		if (OidIsValid(toastrelid))
 		{

src/backend/rewrite/rewriteHandler.c

@@ -131,9 +131,9 @@ AcquireRewriteLocks(Query *parsetree, bool forUpdatePushedDown)
 				 *
 				 * If the relation is the query's result relation, then we
 				 * need RowExclusiveLock.  Otherwise, check to see if the
-				 * relation is accessed FOR [KEY] UPDATE/SHARE or not.  We can't
+				 * relation is accessed FOR [KEY] UPDATE/SHARE or not.	We
-				 * just grab AccessShareLock because then the executor would
+				 * can't just grab AccessShareLock because then the executor
-				 * be trying to upgrade the lock, leading to possible
+				 * would be trying to upgrade the lock, leading to possible
 				 * deadlocks.
 				 */
 				if (rt_index == parsetree->resultRelation)
@@ -1375,8 +1375,8 @@ ApplyRetrieveRule(Query *parsetree,
 	}
 
 	/*
-	 * If FOR [KEY] UPDATE/SHARE of view, be sure we get right initial lock on the
+	 * If FOR [KEY] UPDATE/SHARE of view, be sure we get right initial lock on
-	 * relations it references.
+	 * the relations it references.
 	 */
 	rc = get_parse_rowmark(parsetree, rt_index);
 	forUpdatePushedDown |= (rc != NULL);
@@ -1423,9 +1423,9 @@ ApplyRetrieveRule(Query *parsetree,
 	rte->modifiedCols = NULL;
 
 	/*
-	 * If FOR [KEY] UPDATE/SHARE of view, mark all the contained tables as implicit
+	 * If FOR [KEY] UPDATE/SHARE of view, mark all the contained tables as
-	 * FOR [KEY] UPDATE/SHARE, the same as the parser would have done if the view's
+	 * implicit FOR [KEY] UPDATE/SHARE, the same as the parser would have done
-	 * subquery had been written out explicitly.
+	 * if the view's subquery had been written out explicitly.
 	 *
 	 * Note: we don't consider forUpdatePushedDown here; such marks will be
 	 * made by recursing from the upper level in markQueryForLocking.
@@ -2089,9 +2089,9 @@ relation_is_updatable(Oid reloid, int req_events)
 
 	/*
 	 * If the relation doesn't exist, say "false" rather than throwing an
-	 * error.  This is helpful since scanning an information_schema view
+	 * error.  This is helpful since scanning an information_schema view under
-	 * under MVCC rules can result in referencing rels that were just
+	 * MVCC rules can result in referencing rels that were just deleted
-	 * deleted according to a SnapshotNow probe.
+	 * according to a SnapshotNow probe.
 	 */
 	if (rel == NULL)
 		return false;
@@ -2680,10 +2680,10 @@ RewriteQuery(Query *parsetree, List *rewrite_events)
 			parsetree = rewriteTargetView(parsetree, rt_entry_relation);
 
 			/*
-			 * At this point product_queries contains any DO ALSO rule actions.
+			 * At this point product_queries contains any DO ALSO rule
-			 * Add the rewritten query before or after those.  This must match
+			 * actions. Add the rewritten query before or after those.	This
-			 * the handling the original query would have gotten below, if
+			 * must match the handling the original query would have gotten
-			 * we allowed it to be included again.
+			 * below, if we allowed it to be included again.
 			 */
 			if (parsetree->commandType == CMD_INSERT)
 				product_queries = lcons(parsetree, product_queries);

src/backend/rewrite/rewriteManip.c

@@ -1406,6 +1406,7 @@ ReplaceVarsFromTargetList_callback(Var *var,
 				return (Node *) var;
 
 			case REPLACEVARS_SUBSTITUTE_NULL:
+
 				/*
 				 * If Var is of domain type, we should add a CoerceToDomain
 				 * node, in case there is a NOT NULL domain constraint.

src/backend/storage/buffer/bufmgr.c

@@ -1220,7 +1220,8 @@ BufferSync(int flags)
 
 	/*
 	 * Unless this is a shutdown checkpoint, we write only permanent, dirty
-	 * buffers.  But at shutdown or end of recovery, we write all dirty buffers.
+	 * buffers.  But at shutdown or end of recovery, we write all dirty
+	 * buffers.
 	 */
 	if (!((flags & CHECKPOINT_IS_SHUTDOWN) || (flags & CHECKPOINT_END_OF_RECOVERY)))
 		mask |= BM_PERMANENT;
@@ -1964,14 +1965,14 @@ FlushBuffer(volatile BufferDesc *buf, SMgrRelation reln)
 	 * However, this rule does not apply to unlogged relations, which will be
 	 * lost after a crash anyway.  Most unlogged relation pages do not bear
 	 * LSNs since we never emit WAL records for them, and therefore flushing
-	 * up through the buffer LSN would be useless, but harmless.  However, GiST
+	 * up through the buffer LSN would be useless, but harmless.  However,
-	 * indexes use LSNs internally to track page-splits, and therefore unlogged
+	 * GiST indexes use LSNs internally to track page-splits, and therefore
-	 * GiST pages bear "fake" LSNs generated by GetFakeLSNForUnloggedRel.  It
+	 * unlogged GiST pages bear "fake" LSNs generated by
-	 * is unlikely but possible that the fake LSN counter could advance past
+	 * GetFakeLSNForUnloggedRel.  It is unlikely but possible that the fake
-	 * the WAL insertion point; and if it did happen, attempting to flush WAL
+	 * LSN counter could advance past the WAL insertion point; and if it did
-	 * through that location would fail, with disastrous system-wide
+	 * happen, attempting to flush WAL through that location would fail, with
-	 * consequences.  To make sure that can't happen, skip the flush if the
+	 * disastrous system-wide consequences.  To make sure that can't happen,
-	 * buffer isn't permanent.
+	 * skip the flush if the buffer isn't permanent.
 	 */
 	if (buf->flags & BM_PERMANENT)
 		XLogFlush(recptr);
@@ -2204,8 +2205,8 @@ DropRelFileNodesAllBuffers(RelFileNodeBackend *rnodes, int nnodes)
 	}
 
 	/*
-	 * If there are no non-local relations, then we're done. Release the memory
+	 * If there are no non-local relations, then we're done. Release the
-	 * and return.
+	 * memory and return.
 	 */
 	if (n == 0)
 	{
@@ -2215,8 +2216,8 @@ DropRelFileNodesAllBuffers(RelFileNodeBackend *rnodes, int nnodes)
 
 	/*
 	 * For low number of relations to drop just use a simple walk through, to
-	 * save the bsearch overhead. The threshold to use is rather a guess than a
+	 * save the bsearch overhead. The threshold to use is rather a guess than
-	 * exactly determined value, as it depends on many factors (CPU and RAM
+	 * a exactly determined value, as it depends on many factors (CPU and RAM
 	 * speeds, amount of shared buffers etc.).
 	 */
 	use_bsearch = n > DROP_RELS_BSEARCH_THRESHOLD;
@@ -2605,13 +2606,13 @@ MarkBufferDirtyHint(Buffer buffer)
 	/*
 	 * This routine might get called many times on the same page, if we are
 	 * making the first scan after commit of an xact that added/deleted many
-	 * tuples. So, be as quick as we can if the buffer is already dirty.  We do
+	 * tuples. So, be as quick as we can if the buffer is already dirty.  We
-	 * this by not acquiring spinlock if it looks like the status bits are
+	 * do this by not acquiring spinlock if it looks like the status bits are
 	 * already set.  Since we make this test unlocked, there's a chance we
 	 * might fail to notice that the flags have just been cleared, and failed
 	 * to reset them, due to memory-ordering issues.  But since this function
-	 * is only intended to be used in cases where failing to write out the data
+	 * is only intended to be used in cases where failing to write out the
-	 * would be harmless anyway, it doesn't really matter.
+	 * data would be harmless anyway, it doesn't really matter.
 	 */
 	if ((bufHdr->flags & (BM_DIRTY | BM_JUST_DIRTIED)) !=
 		(BM_DIRTY | BM_JUST_DIRTIED))
@@ -2622,21 +2623,20 @@ MarkBufferDirtyHint(Buffer buffer)
 
 		/*
 		 * If checksums are enabled, and the buffer is permanent, then a full
-		 * page image may be required even for some hint bit updates to protect
+		 * page image may be required even for some hint bit updates to
-		 * against torn pages. This full page image is only necessary if the
+		 * protect against torn pages. This full page image is only necessary
-		 * hint bit update is the first change to the page since the last
+		 * if the hint bit update is the first change to the page since the
-		 * checkpoint.
+		 * last checkpoint.
 		 *
-		 * We don't check full_page_writes here because that logic is
+		 * We don't check full_page_writes here because that logic is included
-		 * included when we call XLogInsert() since the value changes
+		 * when we call XLogInsert() since the value changes dynamically.
-		 * dynamically.
 		 */
 		if (DataChecksumsEnabled() && (bufHdr->flags & BM_PERMANENT))
 		{
 			/*
 			 * If we're in recovery we cannot dirty a page because of a hint.
-			 * We can set the hint, just not dirty the page as a result so
+			 * We can set the hint, just not dirty the page as a result so the
-			 * the hint is lost when we evict the page or shutdown.
+			 * hint is lost when we evict the page or shutdown.
 			 *
 			 * See src/backend/storage/page/README for longer discussion.
 			 */
@@ -2646,21 +2646,21 @@ MarkBufferDirtyHint(Buffer buffer)
 			/*
 			 * If the block is already dirty because we either made a change
 			 * or set a hint already, then we don't need to write a full page
-			 * image.  Note that aggressive cleaning of blocks
+			 * image.  Note that aggressive cleaning of blocks dirtied by hint
-			 * dirtied by hint bit setting would increase the call rate.
+			 * bit setting would increase the call rate. Bulk setting of hint
-			 * Bulk setting of hint bits would reduce the call rate...
+			 * bits would reduce the call rate...
 			 *
 			 * We must issue the WAL record before we mark the buffer dirty.
-			 * Otherwise we might write the page before we write the WAL.
+			 * Otherwise we might write the page before we write the WAL. That
-			 * That causes a race condition, since a checkpoint might occur
+			 * causes a race condition, since a checkpoint might occur between
-			 * between writing the WAL record and marking the buffer dirty.
+			 * writing the WAL record and marking the buffer dirty. We solve
-			 * We solve that with a kluge, but one that is already in use
+			 * that with a kluge, but one that is already in use during
-			 * during transaction commit to prevent race conditions.
+			 * transaction commit to prevent race conditions. Basically, we
-			 * Basically, we simply prevent the checkpoint WAL record from
+			 * simply prevent the checkpoint WAL record from being written
-			 * being written until we have marked the buffer dirty. We don't
+			 * until we have marked the buffer dirty. We don't start the
-			 * start the checkpoint flush until we have marked dirty, so our
+			 * checkpoint flush until we have marked dirty, so our checkpoint
-			 * checkpoint must flush the change to disk successfully or the
+			 * must flush the change to disk successfully or the checkpoint
-			 * checkpoint never gets written, so crash recovery will fix.
+			 * never gets written, so crash recovery will fix.
 			 *
 			 * It's possible we may enter here without an xid, so it is
 			 * essential that CreateCheckpoint waits for virtual transactions
@@ -2677,13 +2677,13 @@ MarkBufferDirtyHint(Buffer buffer)
 			dirtied = true;		/* Means "will be dirtied by this action" */
 
 			/*
-			 * Set the page LSN if we wrote a backup block. We aren't
+			 * Set the page LSN if we wrote a backup block. We aren't supposed
-			 * supposed to set this when only holding a share lock but
+			 * to set this when only holding a share lock but as long as we
-			 * as long as we serialise it somehow we're OK. We choose to
+			 * serialise it somehow we're OK. We choose to set LSN while
-			 * set LSN while holding the buffer header lock, which causes
+			 * holding the buffer header lock, which causes any reader of an
-			 * any reader of an LSN who holds only a share lock to also
+			 * LSN who holds only a share lock to also obtain a buffer header
-			 * obtain a buffer header lock before using PageGetLSN(),
+			 * lock before using PageGetLSN(), which is enforced in
-			 * which is enforced in BufferGetLSNAtomic().
+			 * BufferGetLSNAtomic().
 			 *
 			 * If checksums are enabled, you might think we should reset the
 			 * checksum here. That will happen when the page is written

src/backend/storage/ipc/procarray.c

@@ -1429,11 +1429,11 @@ GetSnapshotData(Snapshot snapshot)
 		 * depending upon when the snapshot was taken, or change normal
 		 * snapshot processing so it matches.
 		 *
-		 * Note: It is possible for recovery to end before we finish taking the
+		 * Note: It is possible for recovery to end before we finish taking
-		 * snapshot, and for newly assigned transaction ids to be added to the
+		 * the snapshot, and for newly assigned transaction ids to be added to
-		 * ProcArray.  xmax cannot change while we hold ProcArrayLock, so those
+		 * the ProcArray.  xmax cannot change while we hold ProcArrayLock, so
-		 * newly added transaction ids would be filtered away, so we need not
+		 * those newly added transaction ids would be filtered away, so we
-		 * be concerned about them.
+		 * need not be concerned about them.
 		 */
 		subcount = KnownAssignedXidsGetAndSetXmin(snapshot->subxip, &xmin,
 												  xmax);
@@ -1688,8 +1688,8 @@ GetRunningTransactionData(void)
 
 				/*
 				 * Top-level XID of a transaction is always less than any of
-				 * its subxids, so we don't need to check if any of the subxids
+				 * its subxids, so we don't need to check if any of the
-				 * are smaller than oldestRunningXid
+				 * subxids are smaller than oldestRunningXid
 				 */
 			}
 		}

src/backend/storage/ipc/standby.c

@@ -443,10 +443,10 @@ ResolveRecoveryConflictWithBufferPin(void)
 	ProcWaitForSignal();
 
 	/*
-	 * Clear any timeout requests established above.  We assume here that
+	 * Clear any timeout requests established above.  We assume here that the
-	 * the Startup process doesn't have any other timeouts than what this
+	 * Startup process doesn't have any other timeouts than what this function
-	 * function uses.  If that stops being true, we could cancel the
+	 * uses.  If that stops being true, we could cancel the timeouts
-	 * timeouts individually, but that'd be slower.
+	 * individually, but that'd be slower.
 	 */
 	disable_all_timeouts(false);
 }

src/backend/storage/lmgr/lock.c

@@ -2333,8 +2333,8 @@ LockReassignOwner(LOCALLOCK *locallock, ResourceOwner parent)
 	int			ip = -1;
 
 	/*
-	 * Scan to see if there are any locks belonging to current owner or
+	 * Scan to see if there are any locks belonging to current owner or its
-	 * its parent
+	 * parent
 	 */
 	lockOwners = locallock->lockOwners;
 	for (i = locallock->numLockOwners - 1; i >= 0; i--)
@@ -2690,9 +2690,9 @@ GetLockConflicts(const LOCKTAG *locktag, LOCKMODE lockmode)
 			LWLockAcquire(proc->backendLock, LW_SHARED);
 
 			/*
-			 * If the target backend isn't referencing the same database as the
+			 * If the target backend isn't referencing the same database as
-			 * lock, then we needn't examine the individual relation IDs at
+			 * the lock, then we needn't examine the individual relation IDs
-			 * all; none of them can be relevant.
+			 * at all; none of them can be relevant.
 			 *
 			 * See FastPathTransferLocks() for discussion of why we do this
 			 * test after acquiring the lock.
@@ -3165,8 +3165,8 @@ PostPrepare_Locks(TransactionId xid)
 			 * our procLink chain and put it into the new proc's chain, too.
 			 *
 			 * Note: the updated proclock hash key will still belong to the
-			 * same hash partition, cf proclock_hash().  So the partition
+			 * same hash partition, cf proclock_hash().  So the partition lock
-			 * lock we already hold is sufficient for this.
+			 * we already hold is sufficient for this.
 			 */
 			SHMQueueDelete(&proclock->procLink);
 
@@ -3177,9 +3177,9 @@ PostPrepare_Locks(TransactionId xid)
 			proclocktag.myProc = newproc;
 
 			/*
-			 * Update the proclock.  We should not find any existing entry
+			 * Update the proclock.  We should not find any existing entry for
-			 * for the same hash key, since there can be only one entry for
+			 * the same hash key, since there can be only one entry for any
-			 * any given lock with my own proc.
+			 * given lock with my own proc.
 			 */
 			if (!hash_update_hash_key(LockMethodProcLockHash,
 									  (void *) proclock,

src/backend/storage/lmgr/predicate.c

@@ -1575,8 +1575,8 @@ GetSerializableTransactionSnapshot(Snapshot snapshot)
 
 	/*
 	 * Can't use serializable mode while recovery is still active, as it is,
-	 * for example, on a hot standby.  We could get here despite the check
+	 * for example, on a hot standby.  We could get here despite the check in
-	 * in check_XactIsoLevel() if default_transaction_isolation is set to
+	 * check_XactIsoLevel() if default_transaction_isolation is set to
 	 * serializable, so phrase the hint accordingly.
 	 */
 	if (RecoveryInProgress())

src/backend/storage/lmgr/proc.c

@@ -186,8 +186,8 @@ InitProcGlobal(void)
 	 * five separate consumers: (1) normal backends, (2) autovacuum workers
 	 * and the autovacuum launcher, (3) background workers, (4) auxiliary
 	 * processes, and (5) prepared transactions.  Each PGPROC structure is
-	 * dedicated to exactly one of these purposes, and they do not move between
+	 * dedicated to exactly one of these purposes, and they do not move
-	 * groups.
+	 * between groups.
 	 */
 	procs = (PGPROC *) ShmemAlloc(TotalProcs * sizeof(PGPROC));
 	ProcGlobal->allProcs = procs;

src/backend/storage/page/bufpage.c

@@ -101,10 +101,10 @@ PageIsVerified(Page page, BlockNumber blkno)
 		}
 
 		/*
-		 * The following checks don't prove the header is correct,
+		 * The following checks don't prove the header is correct, only that
-		 * only that it looks sane enough to allow into the buffer pool.
+		 * it looks sane enough to allow into the buffer pool. Later usage of
-		 * Later usage of the block can still reveal problems,
+		 * the block can still reveal problems, which is why we offer the
-		 * which is why we offer the checksum option.
+		 * checksum option.
 		 */
 		if ((p->pd_flags & ~PD_VALID_FLAG_BITS) == 0 &&
 			p->pd_lower <= p->pd_upper &&
@@ -905,10 +905,10 @@ PageSetChecksumCopy(Page page, BlockNumber blkno)
 
 	/*
 	 * We make a copy iff we need to calculate a checksum because other
-	 * backends may set hint bits on this page while we write, which
+	 * backends may set hint bits on this page while we write, which would
-	 * would mean the checksum differs from the page contents. It doesn't
+	 * mean the checksum differs from the page contents. It doesn't matter if
-	 * matter if we include or exclude hints during the copy, as long
+	 * we include or exclude hints during the copy, as long as we write a
-	 * as we write a valid page and associated checksum.
+	 * valid page and associated checksum.
 	 */
 	memcpy((char *) pageCopy, (char *) page, BLCKSZ);
 	PageSetChecksumInplace(pageCopy, blkno);
@@ -931,6 +931,7 @@ PageSetChecksumInplace(Page page, BlockNumber blkno)
 	if (DataChecksumsEnabled())
 	{
 		PageHeader	p = (PageHeader) page;
+
 		p->pd_checksum = PageCalcChecksum16(page, blkno);
 	}
 
@@ -958,9 +959,8 @@ PageCalcChecksum16(Page page, BlockNumber blkno)
 
 	/*
 	 * Save pd_checksum and set it to zero, so that the checksum calculation
-	 * isn't affected by the checksum stored on the page. We do this to
+	 * isn't affected by the checksum stored on the page. We do this to allow
-	 * allow optimization of the checksum calculation on the whole block
+	 * optimization of the checksum calculation on the whole block in one go.
-	 * in one go.
 	 */
 	save_checksum = phdr->pd_checksum;
 	phdr->pd_checksum = 0;

src/backend/storage/page/checksum.c

@@ -134,7 +134,8 @@ checksum_block(char *data, uint32 size)
 	uint32		sums[N_SUMS];
 	uint32		(*dataArr)[N_SUMS] = (uint32 (*)[N_SUMS]) data;
 	uint32		result = 0;
-	int i, j;
+	int			i,
+				j;
 
 	/* ensure that the size is compatible with the algorithm */
 	Assert((size % (sizeof(uint32) * N_SUMS)) == 0);

src/backend/storage/smgr/smgr.c

@@ -443,8 +443,8 @@ smgrdounlinkall(SMgrRelation *rels, int nrels, bool isRedo)
 		return;
 
 	/*
-	 * create an array which contains all relations to be dropped, and
+	 * create an array which contains all relations to be dropped, and close
-	 * close each relation's forks at the smgr level while at it
+	 * each relation's forks at the smgr level while at it
 	 */
 	rnodes = palloc(sizeof(RelFileNodeBackend) * nrels);
 	for (i = 0; i < nrels; i++)
@@ -466,8 +466,8 @@ smgrdounlinkall(SMgrRelation *rels, int nrels, bool isRedo)
 	DropRelFileNodesAllBuffers(rnodes, nrels);
 
 	/*
-	 * It'd be nice to tell the stats collector to forget them immediately, too.
+	 * It'd be nice to tell the stats collector to forget them immediately,
-	 * But we can't because we don't know the OIDs.
+	 * too. But we can't because we don't know the OIDs.
 	 */
 
 	/*
@@ -475,8 +475,8 @@ smgrdounlinkall(SMgrRelation *rels, int nrels, bool isRedo)
 	 * dangling smgr references they may have for these rels.  We should do
 	 * this before starting the actual unlinking, in case we fail partway
 	 * through that step.  Note that the sinval messages will eventually come
-	 * back to this backend, too, and thereby provide a backstop that we closed
+	 * back to this backend, too, and thereby provide a backstop that we
-	 * our own smgr rel.
+	 * closed our own smgr rel.
 	 */
 	for (i = 0; i < nrels; i++)
 		CacheInvalidateSmgr(rnodes[i]);
@@ -492,6 +492,7 @@ smgrdounlinkall(SMgrRelation *rels, int nrels, bool isRedo)
 	for (i = 0; i < nrels; i++)
 	{
 		int			which = rels[i]->smgr_which;
+
 		for (forknum = 0; forknum <= MAX_FORKNUM; forknum++)
 			(*(smgrsw[which].smgr_unlink)) (rnodes[i], forknum, isRedo);
 	}

src/backend/utils/adt/array_typanalyze.c

@@ -388,8 +388,8 @@ compute_array_stats(VacAttrStats *stats, AnalyzeAttrFetchFunc fetchfunc,
 
 				/*
 				 * If element type is pass-by-reference, we must copy it into
-				 * palloc'd space, so that we can release the array below.
+				 * palloc'd space, so that we can release the array below. (We
-				 * (We do this so that the space needed for element values is
+				 * do this so that the space needed for element values is
 				 * limited by the size of the hashtable; if we kept all the
 				 * array values around, it could be much more.)
 				 */