diff --git a/contrib/pg_upgrade/pg_upgrade.c b/contrib/pg_upgrade/pg_upgrade.c
index 63df52996d5..c12f15b875b 100644
--- a/contrib/pg_upgrade/pg_upgrade.c
+++ b/contrib/pg_upgrade/pg_upgrade.c
@@ -150,12 +150,6 @@ main(int argc, char **argv)
 			  new_cluster.pgdata);
 	check_ok();
 
-	prep_status("Sync data directory to disk");
-	exec_prog(UTILITY_LOG_FILE, NULL, true,
-			  "\"%s/initdb\" --sync-only \"%s\"", new_cluster.bindir,
-			  new_cluster.pgdata);
-	check_ok();
-
 	create_script_for_cluster_analyze(&analyze_script_file_name);
 	create_script_for_old_cluster_deletion(&deletion_script_file_name);
 
diff --git a/contrib/pg_upgrade/server.c b/contrib/pg_upgrade/server.c
index db622496372..49d4c8f9d73 100644
--- a/contrib/pg_upgrade/server.c
+++ b/contrib/pg_upgrade/server.c
@@ -209,10 +209,9 @@ start_postmaster(ClusterInfo *cluster)
 	 * a gap of 2000000000 from the current xid counter, so autovacuum will
 	 * not touch them.
 	 *
-	 * Turn off durability requirements to improve object creation speed, and
-	 * we only modify the new cluster, so only use it there.  If there is a
-	 * crash, the new cluster has to be recreated anyway.  fsync=off is a big
-	 * win on ext4.
+	 *	synchronous_commit=off improves object creation speed, and we only
+	 *	modify the new cluster, so only use it there.  If there is a crash,
+	 *	the new cluster has to be recreated anyway.
 	 */
 	snprintf(cmd, sizeof(cmd),
 			 "\"%s/pg_ctl\" -w -l \"%s\" -D \"%s\" -o \"-p %d%s%s%s%s\" start",
@@ -220,8 +219,7 @@ start_postmaster(ClusterInfo *cluster)
 			 (cluster->controldata.cat_ver >=
 			  BINARY_UPGRADE_SERVER_FLAG_CAT_VER) ? " -b" :
 			 " -c autovacuum=off -c autovacuum_freeze_max_age=2000000000",
-			 (cluster == &new_cluster) ?
-				" -c synchronous_commit=off -c fsync=off -c full_page_writes=off" : "",
+			 (cluster == &new_cluster) ? " -c synchronous_commit=off" : "",
 			 cluster->pgopts ? cluster->pgopts : "", socket_string);
 
 	/*
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index b7df8ce6124..b56070b0fb9 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -1696,15 +1696,6 @@ include 'filename'
         turning off <varname>fsync</varname>.
        </para>
 
-       <para>
-        For reliable recovery when changing <varname>fsync</varname>
-        off to on, it is necessary to force all modified buffers in the
-        kernel to durable storage.  This can be done while the cluster
-        is shutdown or while fsync is on by running <command>initdb
-        --sync-only</command>, running <command>sync</>, unmounting the
-        file system, or rebooting the server.
-       </para>
-
        <para>
         In many situations, turning off <xref linkend="guc-synchronous-commit">
         for noncritical transactions can provide much of the potential
diff --git a/doc/src/sgml/ref/initdb.sgml b/doc/src/sgml/ref/initdb.sgml
index a1e46eb4c67..08ee37e7d86 100644
--- a/doc/src/sgml/ref/initdb.sgml
+++ b/doc/src/sgml/ref/initdb.sgml
@@ -244,17 +244,6 @@ PostgreSQL documentation
       </listitem>
      </varlistentry>
 
-     <varlistentry>
-      <term><option>-S</option></term>
-      <term><option>--sync-only</option></term>
-      <listitem>
-       <para>
-        Safely write all database files to disk and exit.  This does not
-        perform any of the normal <application>initdb</> operations.
-       </para>
-      </listitem>
-     </varlistentry>
-
      <varlistentry>
       <term><option>-T <replaceable>CFG</></option></term>
       <term><option>--text-search-config=<replaceable>CFG</></option></term>
diff --git a/src/bin/initdb/initdb.c b/src/bin/initdb/initdb.c
index 8c0a9f41abf..402504b2578 100644
--- a/src/bin/initdb/initdb.c
+++ b/src/bin/initdb/initdb.c
@@ -118,7 +118,6 @@ static const char *authmethodlocal = "";
 static bool debug = false;
 static bool noclean = false;
 static bool do_sync = true;
-static bool sync_only = false;
 static bool show_setting = false;
 static char *xlog_dir = "";
 
@@ -2797,7 +2796,6 @@ usage(const char *progname)
 	printf(_("  -n, --noclean             do not clean up after errors\n"));
 	printf(_("  -N, --nosync              do not wait for changes to be written safely to disk\n"));
 	printf(_("  -s, --show                show internal settings\n"));
-	printf(_("  -S, --sync-only           only sync data directory\n"));
 	printf(_("\nOther options:\n"));
 	printf(_("  -V, --version             output version information, then exit\n"));
 	printf(_("  -?, --help                show this help, then exit\n"));
@@ -3447,7 +3445,6 @@ main(int argc, char *argv[])
 		{"show", no_argument, NULL, 's'},
 		{"noclean", no_argument, NULL, 'n'},
 		{"nosync", no_argument, NULL, 'N'},
-		{"sync-only", no_argument, NULL, 'S'},
 		{"xlogdir", required_argument, NULL, 'X'},
 		{NULL, 0, NULL, 0}
 	};
@@ -3479,7 +3476,7 @@ main(int argc, char *argv[])
 
 	/* process command-line options */
 
-	while ((c = getopt_long(argc, argv, "dD:E:L:nNU:WA:sST:X:", long_options, &option_index)) != -1)
+	while ((c = getopt_long(argc, argv, "dD:E:L:nNU:WA:sT:X:", long_options, &option_index)) != -1)
 	{
 		switch (c)
 		{
@@ -3525,9 +3522,6 @@ main(int argc, char *argv[])
 			case 'N':
 				do_sync = false;
 				break;
-			case 'S':
-				sync_only = true;
-				break;
 			case 'L':
 				share_path = pg_strdup(optarg);
 				break;
@@ -3595,14 +3589,6 @@ main(int argc, char *argv[])
 		exit(1);
 	}
 
-	/* If we only need to fsync, just to it and exit */
-	if (sync_only)
-	{
-		setup_pgdata();
-		perform_fsync();
-		return 0;
-	}
-	
 	if (pwprompt && pwfilename)
 	{
 		fprintf(stderr, _("%s: password prompt and password file cannot be specified together\n"), progname);