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Add a function pg_stat_clear_snapshot() that discards any statistics snapshot
already collected in the current transaction; this allows plpgsql functions to watch for stats updates even though they are confined to a single transaction. Use this instead of the previous kluge involving pg_stat_file() to wait for the stats collector to update in the stats regression test. Internally, decouple storage of stats snapshots from transaction boundaries; they'll now stick around until someone calls pgstat_clear_snapshot --- which xact.c still does at transaction end, to maintain the previous behavior. This makes the logic a lot cleaner, at the price of a couple dozen cycles per transaction exit.
This commit is contained in:
Tom Lane
@ -10,7 +10,7 @@
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*
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.232 2007/02/01 19:10:25 momjian Exp $
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* $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.233 2007/02/07 23:11:29 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -1628,6 +1628,7 @@ CommitTransaction(void)
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AtEOXact_Namespace(true);
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/* smgrcommit already done */
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AtEOXact_Files();
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pgstat_clear_snapshot();
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pgstat_count_xact_commit();
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pgstat_report_txn_timestamp(0);
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@ -1844,6 +1845,7 @@ PrepareTransaction(void)
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AtEOXact_Namespace(true);
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/* smgrcommit already done */
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AtEOXact_Files();
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pgstat_clear_snapshot();
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CurrentResourceOwner = NULL;
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ResourceOwnerDelete(TopTransactionResourceOwner);
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@ -1995,6 +1997,7 @@ AbortTransaction(void)
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AtEOXact_Namespace(false);
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smgrabort();
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AtEOXact_Files();
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pgstat_clear_snapshot();
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pgstat_count_xact_rollback();
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pgstat_report_txn_timestamp(0);
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@ -13,7 +13,7 @@
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*
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* Copyright (c) 2001-2007, PostgreSQL Global Development Group
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*
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* $PostgreSQL: pgsql/src/backend/postmaster/pgstat.c,v 1.144 2007/01/26 20:06:52 tgl Exp $
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* $PostgreSQL: pgsql/src/backend/postmaster/pgstat.c,v 1.145 2007/02/07 23:11:29 tgl Exp $
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* ----------
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*/
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#include "postgres.h"
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@ -130,9 +130,8 @@ static TabStatArray SharedTabStat = {0, 0, NULL};
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static int pgStatXactCommit = 0;
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static int pgStatXactRollback = 0;
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static TransactionId pgStatDBHashXact = InvalidTransactionId;
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static MemoryContext pgStatLocalContext = NULL;
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static HTAB *pgStatDBHash = NULL;
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static TransactionId pgStatLocalStatusXact = InvalidTransactionId;
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static PgBackendStatus *localBackendStatusTable = NULL;
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static int localNumBackends = 0;
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@ -156,11 +155,13 @@ static void pgstat_beshutdown_hook(int code, Datum arg);
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static PgStat_StatDBEntry *pgstat_get_db_entry(Oid databaseid, bool create);
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static void pgstat_drop_database(Oid databaseid);
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static void pgstat_write_statsfile(void);
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static void pgstat_read_statsfile(HTAB **dbhash, Oid onlydb);
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static HTAB *pgstat_read_statsfile(Oid onlydb);
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static void backend_read_statsfile(void);
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static void pgstat_read_current_status(void);
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static HTAB *pgstat_collect_oids(Oid catalogid);
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static void pgstat_setup_memcxt(void);
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static void pgstat_setheader(PgStat_MsgHdr *hdr, StatMsgType mtype);
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static void pgstat_send(void *msg, int len);
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@ -1535,22 +1536,24 @@ pgstat_report_waiting(bool waiting)
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static void
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pgstat_read_current_status(void)
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{
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TransactionId topXid = GetTopTransactionId();
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volatile PgBackendStatus *beentry;
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PgBackendStatus *localtable;
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PgBackendStatus *localentry;
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int i;
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Assert(!pgStatRunningInCollector);
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if (TransactionIdEquals(pgStatLocalStatusXact, topXid))
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if (localBackendStatusTable)
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return; /* already done */
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localBackendStatusTable = (PgBackendStatus *)
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MemoryContextAlloc(TopTransactionContext,
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pgstat_setup_memcxt();
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localtable = (PgBackendStatus *)
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MemoryContextAlloc(pgStatLocalContext,
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sizeof(PgBackendStatus) * MaxBackends);
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localNumBackends = 0;
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beentry = BackendStatusArray;
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localentry = localBackendStatusTable;
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localentry = localtable;
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for (i = 1; i <= MaxBackends; i++)
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{
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/*
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@ -1587,7 +1590,8 @@ pgstat_read_current_status(void)
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}
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}
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pgStatLocalStatusXact = topXid;
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/* Set the pointer only after completion of a valid table */
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localBackendStatusTable = localtable;
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}
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@ -1720,7 +1724,7 @@ PgstatCollectorMain(int argc, char *argv[])
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* zero.
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*/
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pgStatRunningInCollector = true;
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pgstat_read_statsfile(&pgStatDBHash, InvalidOid);
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pgStatDBHash = pgstat_read_statsfile(InvalidOid);
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/*
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* Setup the descriptor set for select(2). Since only one bit in the set
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@ -2090,38 +2094,24 @@ pgstat_write_statsfile(void)
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* databases' hash table (whose entries point to the tables' hash tables).
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* ----------
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*/
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static void
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pgstat_read_statsfile(HTAB **dbhash, Oid onlydb)
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static HTAB *
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pgstat_read_statsfile(Oid onlydb)
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{
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PgStat_StatDBEntry *dbentry;
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PgStat_StatDBEntry dbbuf;
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PgStat_StatTabEntry *tabentry;
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PgStat_StatTabEntry tabbuf;
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HASHCTL hash_ctl;
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HTAB *dbhash;
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HTAB *tabhash = NULL;
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FILE *fpin;
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int32 format_id;
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bool found;
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MemoryContext use_mcxt;
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int mcxt_flags;
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/*
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* If running in the collector or the autovacuum process, we use the
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* DynaHashCxt memory context. If running in a backend, we use the
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* TopTransactionContext instead, so the caller must only know the last
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* XactId when this call happened to know if his tables are still valid or
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* already gone!
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* The tables will live in pgStatLocalContext.
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*/
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if (pgStatRunningInCollector || IsAutoVacuumProcess())
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{
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use_mcxt = NULL;
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mcxt_flags = 0;
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}
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else
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{
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use_mcxt = TopTransactionContext;
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mcxt_flags = HASH_CONTEXT;
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}
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pgstat_setup_memcxt();
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/*
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* Create the DB hashtable
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@ -2130,9 +2120,9 @@ pgstat_read_statsfile(HTAB **dbhash, Oid onlydb)
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hash_ctl.keysize = sizeof(Oid);
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hash_ctl.entrysize = sizeof(PgStat_StatDBEntry);
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hash_ctl.hash = oid_hash;
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hash_ctl.hcxt = use_mcxt;
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*dbhash = hash_create("Databases hash", PGSTAT_DB_HASH_SIZE, &hash_ctl,
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HASH_ELEM | HASH_FUNCTION | mcxt_flags);
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hash_ctl.hcxt = pgStatLocalContext;
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dbhash = hash_create("Databases hash", PGSTAT_DB_HASH_SIZE, &hash_ctl,
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HASH_ELEM | HASH_FUNCTION | HASH_CONTEXT);
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/*
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* Try to open the status file. If it doesn't exist, the backends simply
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@ -2140,7 +2130,7 @@ pgstat_read_statsfile(HTAB **dbhash, Oid onlydb)
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* with empty counters.
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*/
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if ((fpin = AllocateFile(PGSTAT_STAT_FILENAME, PG_BINARY_R)) == NULL)
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return;
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return dbhash;
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/*
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* Verify it's of the expected format.
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@ -2178,7 +2168,7 @@ pgstat_read_statsfile(HTAB **dbhash, Oid onlydb)
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/*
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* Add to the DB hash
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*/
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dbentry = (PgStat_StatDBEntry *) hash_search(*dbhash,
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dbentry = (PgStat_StatDBEntry *) hash_search(dbhash,
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(void *) &dbbuf.databaseid,
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HASH_ENTER,
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&found);
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@ -2207,11 +2197,11 @@ pgstat_read_statsfile(HTAB **dbhash, Oid onlydb)
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hash_ctl.keysize = sizeof(Oid);
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hash_ctl.entrysize = sizeof(PgStat_StatTabEntry);
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hash_ctl.hash = oid_hash;
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hash_ctl.hcxt = use_mcxt;
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hash_ctl.hcxt = pgStatLocalContext;
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dbentry->tables = hash_create("Per-database table",
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PGSTAT_TAB_HASH_SIZE,
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&hash_ctl,
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HASH_ELEM | HASH_FUNCTION | mcxt_flags);
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HASH_ELEM | HASH_FUNCTION | HASH_CONTEXT);
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/*
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* Arrange that following 'T's add entries to this database's
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@ -2274,44 +2264,78 @@ pgstat_read_statsfile(HTAB **dbhash, Oid onlydb)
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done:
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FreeFile(fpin);
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return dbhash;
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}
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/*
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* If not done for this transaction, read the statistics collector
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* stats file into some hash tables.
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*
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* Because we store the tables in TopTransactionContext, the result
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* is good for the entire current main transaction.
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*
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* Inside the autovacuum process, the statfile is assumed to be valid
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* "forever", that is one iteration, within one database. This means
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* we only consider the statistics as they were when the autovacuum
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* iteration started.
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* If not already done, read the statistics collector stats file into
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* some hash tables. The results will be kept until pgstat_clear_snapshot()
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* is called (typically, at end of transaction).
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*/
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static void
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backend_read_statsfile(void)
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{
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if (IsAutoVacuumProcess())
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{
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/* already read it? */
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if (pgStatDBHash)
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return;
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Assert(!pgStatRunningInCollector);
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pgstat_read_statsfile(&pgStatDBHash, InvalidOid);
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}
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else
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{
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TransactionId topXid = GetTopTransactionId();
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/* already read it? */
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if (pgStatDBHash)
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return;
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Assert(!pgStatRunningInCollector);
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if (!TransactionIdEquals(pgStatDBHashXact, topXid))
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{
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Assert(!pgStatRunningInCollector);
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pgstat_read_statsfile(&pgStatDBHash, MyDatabaseId);
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pgStatDBHashXact = topXid;
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}
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}
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/* Autovacuum wants stats about all databases */
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if (IsAutoVacuumProcess())
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pgStatDBHash = pgstat_read_statsfile(InvalidOid);
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else
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pgStatDBHash = pgstat_read_statsfile(MyDatabaseId);
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}
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/* ----------
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* pgstat_setup_memcxt() -
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*
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* Create pgStatLocalContext, if not already done.
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* ----------
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*/
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static void
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pgstat_setup_memcxt(void)
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{
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if (!pgStatLocalContext)
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pgStatLocalContext = AllocSetContextCreate(TopMemoryContext,
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"Statistics snapshot",
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ALLOCSET_SMALL_MINSIZE,
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ALLOCSET_SMALL_INITSIZE,
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ALLOCSET_SMALL_MAXSIZE);
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}
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/* ----------
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* pgstat_clear_snapshot() -
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*
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* Discard any data collected in the current transaction. Any subsequent
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* request will cause new snapshots to be read.
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*
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* This is also invoked during transaction commit or abort to discard
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* the no-longer-wanted snapshot.
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* ----------
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*/
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void
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pgstat_clear_snapshot(void)
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{
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/* In an autovacuum process we keep the stats forever */
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if (IsAutoVacuumProcess())
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return;
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/* Release memory, if any was allocated */
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if (pgStatLocalContext)
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MemoryContextDelete(pgStatLocalContext);
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/* Reset variables */
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pgStatLocalContext = NULL;
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pgStatDBHash = NULL;
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localBackendStatusTable = NULL;
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localNumBackends = 0;
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}
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/* ----------
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* pgstat_recv_tabstat() -
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*
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/utils/adt/pgstatfuncs.c,v 1.37 2007/01/05 22:19:41 momjian Exp $
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* $PostgreSQL: pgsql/src/backend/utils/adt/pgstatfuncs.c,v 1.38 2007/02/07 23:11:29 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -39,7 +39,6 @@ extern Datum pg_stat_get_last_autoanalyze_time(PG_FUNCTION_ARGS);
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extern Datum pg_stat_get_backend_idset(PG_FUNCTION_ARGS);
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extern Datum pg_backend_pid(PG_FUNCTION_ARGS);
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extern Datum pg_stat_reset(PG_FUNCTION_ARGS);
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extern Datum pg_stat_get_backend_pid(PG_FUNCTION_ARGS);
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extern Datum pg_stat_get_backend_dbid(PG_FUNCTION_ARGS);
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extern Datum pg_stat_get_backend_userid(PG_FUNCTION_ARGS);
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@ -57,6 +56,9 @@ extern Datum pg_stat_get_db_xact_rollback(PG_FUNCTION_ARGS);
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extern Datum pg_stat_get_db_blocks_fetched(PG_FUNCTION_ARGS);
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extern Datum pg_stat_get_db_blocks_hit(PG_FUNCTION_ARGS);
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extern Datum pg_stat_clear_snapshot(PG_FUNCTION_ARGS);
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extern Datum pg_stat_reset(PG_FUNCTION_ARGS);
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Datum
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pg_stat_get_numscans(PG_FUNCTION_ARGS)
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@ -336,16 +338,6 @@ pg_backend_pid(PG_FUNCTION_ARGS)
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PG_RETURN_INT32(MyProcPid);
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}
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/*
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* Built-in function for resetting the counters
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*/
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Datum
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pg_stat_reset(PG_FUNCTION_ARGS)
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{
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pgstat_reset_counters();
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PG_RETURN_BOOL(true);
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}
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Datum
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pg_stat_get_backend_pid(PG_FUNCTION_ARGS)
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@ -678,3 +670,23 @@ pg_stat_get_db_blocks_hit(PG_FUNCTION_ARGS)
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PG_RETURN_INT64(result);
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}
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/* Discard the active statistics snapshot */
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Datum
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pg_stat_clear_snapshot(PG_FUNCTION_ARGS)
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{
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pgstat_clear_snapshot();
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PG_RETURN_VOID();
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}
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/* Reset all counters for the current database */
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Datum
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pg_stat_reset(PG_FUNCTION_ARGS)
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{
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pgstat_reset_counters();
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PG_RETURN_VOID();
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}
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@ -37,7 +37,7 @@
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* Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.381 2007/02/06 02:59:12 tgl Exp $
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* $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.382 2007/02/07 23:11:29 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -53,6 +53,6 @@
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*/
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/* yyyymmddN */
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#define CATALOG_VERSION_NO 200702051
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#define CATALOG_VERSION_NO 200702071
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#endif
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@ -7,7 +7,7 @@
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* Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.442 2007/02/03 14:06:55 petere Exp $
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* $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.443 2007/02/07 23:11:30 tgl Exp $
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*
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* NOTES
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* The script catalog/genbki.sh reads this file and generates .bki
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@ -2938,8 +2938,6 @@ DATA(insert OID = 1936 ( pg_stat_get_backend_idset PGNSP PGUID 12 1 100 f f t
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DESCR("Statistics: Currently active backend IDs");
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DATA(insert OID = 2026 ( pg_backend_pid PGNSP PGUID 12 1 0 f f t f s 0 23 "" _null_ _null_ _null_ pg_backend_pid - _null_ ));
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DESCR("Statistics: Current backend PID");
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DATA(insert OID = 2274 ( pg_stat_reset PGNSP PGUID 12 1 0 f f f f v 0 16 "" _null_ _null_ _null_ pg_stat_reset - _null_ ));
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DESCR("Statistics: Reset collected statistics");
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DATA(insert OID = 1937 ( pg_stat_get_backend_pid PGNSP PGUID 12 1 0 f f t f s 1 23 "23" _null_ _null_ _null_ pg_stat_get_backend_pid - _null_ ));
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DESCR("Statistics: PID of backend");
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DATA(insert OID = 1938 ( pg_stat_get_backend_dbid PGNSP PGUID 12 1 0 f f t f s 1 26 "23" _null_ _null_ _null_ pg_stat_get_backend_dbid - _null_ ));
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@ -2970,6 +2968,10 @@ DATA(insert OID = 1944 ( pg_stat_get_db_blocks_fetched PGNSP PGUID 12 1 0 f f t
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DESCR("Statistics: Blocks fetched for database");
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DATA(insert OID = 1945 ( pg_stat_get_db_blocks_hit PGNSP PGUID 12 1 0 f f t f s 1 20 "26" _null_ _null_ _null_ pg_stat_get_db_blocks_hit - _null_ ));
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DESCR("Statistics: Blocks found in cache for database");
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DATA(insert OID = 2230 ( pg_stat_clear_snapshot PGNSP PGUID 12 1 0 f f f f v 0 2278 "" _null_ _null_ _null_ pg_stat_clear_snapshot - _null_ ));
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DESCR("Statistics: Discard current transaction's statistics snapshot");
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DATA(insert OID = 2274 ( pg_stat_reset PGNSP PGUID 12 1 0 f f f f v 0 2278 "" _null_ _null_ _null_ pg_stat_reset - _null_ ));
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DESCR("Statistics: Reset collected statistics for current database");
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DATA(insert OID = 1946 ( encode PGNSP PGUID 12 1 0 f f t f i 2 25 "17 25" _null_ _null_ _null_ binary_encode - _null_ ));
|
||||
DESCR("Convert bytea value into some ascii-only text string");
|
||||
|
||||
@ -5,7 +5,7 @@
|
||||
*
|
||||
* Copyright (c) 2001-2007, PostgreSQL Global Development Group
|
||||
*
|
||||
* $PostgreSQL: pgsql/src/include/pgstat.h,v 1.52 2007/01/05 22:19:50 momjian Exp $
|
||||
* $PostgreSQL: pgsql/src/include/pgstat.h,v 1.53 2007/02/07 23:11:30 tgl Exp $
|
||||
* ----------
|
||||
*/
|
||||
#ifndef PGSTAT_H
|
||||
@ -380,6 +380,7 @@ extern void pgstat_report_tabstat(void);
|
||||
extern void pgstat_vacuum_tabstat(void);
|
||||
extern void pgstat_drop_relation(Oid relid);
|
||||
|
||||
extern void pgstat_clear_snapshot(void);
|
||||
extern void pgstat_reset_counters(void);
|
||||
|
||||
extern void pgstat_report_autovac(Oid dboid);
|
||||
|
||||
@ -27,6 +27,35 @@ SELECT t.seq_scan, t.seq_tup_read, t.idx_scan, t.idx_tup_fetch,
|
||||
FROM pg_catalog.pg_stat_user_tables AS t,
|
||||
pg_catalog.pg_statio_user_tables AS b
|
||||
WHERE t.relname='tenk2' AND b.relname='tenk2';
|
||||
-- function to wait for counters to advance
|
||||
create function wait_for_stats() returns void as $$
|
||||
declare
|
||||
start_time timestamptz := clock_timestamp();
|
||||
updated bool;
|
||||
begin
|
||||
-- we don't want to wait forever; loop will exit after 30 seconds
|
||||
for i in 1 .. 300 loop
|
||||
|
||||
-- check to see if indexscan has been sensed
|
||||
SELECT (st.idx_scan >= pr.idx_scan + 1) INTO updated
|
||||
FROM pg_stat_user_tables AS st, pg_class AS cl, prevstats AS pr
|
||||
WHERE st.relname='tenk2' AND cl.relname='tenk2';
|
||||
|
||||
exit when updated;
|
||||
|
||||
-- wait a little
|
||||
perform pg_sleep(0.1);
|
||||
|
||||
-- reset stats snapshot so we can test again
|
||||
perform pg_stat_clear_snapshot();
|
||||
|
||||
end loop;
|
||||
|
||||
-- report time waited in postmaster log (where it won't change test output)
|
||||
raise log 'wait_for_stats delayed % seconds',
|
||||
extract(epoch from clock_timestamp() - start_time);
|
||||
end
|
||||
$$ language plpgsql;
|
||||
-- enable statistics
|
||||
SET stats_block_level = on;
|
||||
SET stats_row_level = on;
|
||||
@ -44,58 +73,13 @@ SELECT count(*) FROM tenk2 WHERE unique1 = 1;
|
||||
1
|
||||
(1 row)
|
||||
|
||||
-- All of the thrashing here is to wait for the stats collector to update,
|
||||
-- without waiting too long (in fact, we'd like to try to measure how long
|
||||
-- we wait). Watching for change in the stats themselves wouldn't work
|
||||
-- because the backend only reads them once per transaction. The stats file
|
||||
-- mod timestamp isn't too helpful because it may have resolution of only one
|
||||
-- second, or even worse. So, we touch a new table and then watch for change
|
||||
-- in the size of the stats file. Ugh.
|
||||
-- save current stats-file size
|
||||
CREATE TEMP TABLE prevfilesize AS
|
||||
SELECT size FROM pg_stat_file('global/pgstat.stat');
|
||||
-- make and touch a previously nonexistent table
|
||||
CREATE TABLE stats_hack (f1 int);
|
||||
SELECT * FROM stats_hack;
|
||||
f1
|
||||
----
|
||||
(0 rows)
|
||||
|
||||
-- wait for stats collector to update
|
||||
create function wait_for_stats() returns void as $$
|
||||
declare
|
||||
start_time timestamptz := clock_timestamp();
|
||||
oldsize bigint;
|
||||
newsize bigint;
|
||||
begin
|
||||
-- fetch previous stats-file size
|
||||
select size into oldsize from prevfilesize;
|
||||
|
||||
-- we don't want to wait forever; loop will exit after 30 seconds
|
||||
for i in 1 .. 300 loop
|
||||
|
||||
-- look for update of stats file
|
||||
select size into newsize from pg_stat_file('global/pgstat.stat');
|
||||
|
||||
exit when newsize != oldsize;
|
||||
|
||||
-- wait a little
|
||||
perform pg_sleep(0.1);
|
||||
|
||||
end loop;
|
||||
|
||||
-- report time waited in postmaster log (where it won't change test output)
|
||||
raise log 'wait_for_stats delayed % seconds',
|
||||
extract(epoch from clock_timestamp() - start_time);
|
||||
end
|
||||
$$ language plpgsql;
|
||||
SELECT wait_for_stats();
|
||||
wait_for_stats
|
||||
----------------
|
||||
|
||||
(1 row)
|
||||
|
||||
DROP TABLE stats_hack;
|
||||
-- check effects
|
||||
SELECT st.seq_scan >= pr.seq_scan + 1,
|
||||
st.seq_tup_read >= pr.seq_tup_read + cl.reltuples,
|
||||
|
||||
@ -21,52 +21,28 @@ SELECT t.seq_scan, t.seq_tup_read, t.idx_scan, t.idx_tup_fetch,
|
||||
pg_catalog.pg_statio_user_tables AS b
|
||||
WHERE t.relname='tenk2' AND b.relname='tenk2';
|
||||
|
||||
-- enable statistics
|
||||
SET stats_block_level = on;
|
||||
SET stats_row_level = on;
|
||||
|
||||
-- do a seqscan
|
||||
SELECT count(*) FROM tenk2;
|
||||
-- do an indexscan
|
||||
SELECT count(*) FROM tenk2 WHERE unique1 = 1;
|
||||
|
||||
-- All of the thrashing here is to wait for the stats collector to update,
|
||||
-- without waiting too long (in fact, we'd like to try to measure how long
|
||||
-- we wait). Watching for change in the stats themselves wouldn't work
|
||||
-- because the backend only reads them once per transaction. The stats file
|
||||
-- mod timestamp isn't too helpful because it may have resolution of only one
|
||||
-- second, or even worse. So, we touch a new table and then watch for change
|
||||
-- in the size of the stats file. Ugh.
|
||||
|
||||
-- save current stats-file size
|
||||
CREATE TEMP TABLE prevfilesize AS
|
||||
SELECT size FROM pg_stat_file('global/pgstat.stat');
|
||||
|
||||
-- make and touch a previously nonexistent table
|
||||
CREATE TABLE stats_hack (f1 int);
|
||||
SELECT * FROM stats_hack;
|
||||
|
||||
-- wait for stats collector to update
|
||||
-- function to wait for counters to advance
|
||||
create function wait_for_stats() returns void as $$
|
||||
declare
|
||||
start_time timestamptz := clock_timestamp();
|
||||
oldsize bigint;
|
||||
newsize bigint;
|
||||
updated bool;
|
||||
begin
|
||||
-- fetch previous stats-file size
|
||||
select size into oldsize from prevfilesize;
|
||||
|
||||
-- we don't want to wait forever; loop will exit after 30 seconds
|
||||
for i in 1 .. 300 loop
|
||||
|
||||
-- look for update of stats file
|
||||
select size into newsize from pg_stat_file('global/pgstat.stat');
|
||||
-- check to see if indexscan has been sensed
|
||||
SELECT (st.idx_scan >= pr.idx_scan + 1) INTO updated
|
||||
FROM pg_stat_user_tables AS st, pg_class AS cl, prevstats AS pr
|
||||
WHERE st.relname='tenk2' AND cl.relname='tenk2';
|
||||
|
||||
exit when newsize != oldsize;
|
||||
exit when updated;
|
||||
|
||||
-- wait a little
|
||||
perform pg_sleep(0.1);
|
||||
|
||||
-- reset stats snapshot so we can test again
|
||||
perform pg_stat_clear_snapshot();
|
||||
|
||||
end loop;
|
||||
|
||||
-- report time waited in postmaster log (where it won't change test output)
|
||||
@ -75,9 +51,17 @@ begin
|
||||
end
|
||||
$$ language plpgsql;
|
||||
|
||||
SELECT wait_for_stats();
|
||||
-- enable statistics
|
||||
SET stats_block_level = on;
|
||||
SET stats_row_level = on;
|
||||
|
||||
DROP TABLE stats_hack;
|
||||
-- do a seqscan
|
||||
SELECT count(*) FROM tenk2;
|
||||
-- do an indexscan
|
||||
SELECT count(*) FROM tenk2 WHERE unique1 = 1;
|
||||
|
||||
-- wait for stats collector to update
|
||||
SELECT wait_for_stats();
|
||||
|
||||
-- check effects
|
||||
SELECT st.seq_scan >= pr.seq_scan + 1,
|
||||
|
||||
Reference in New Issue
Block a user