From 4c468b37a281941afd3bf61c782b20def8c17047 Mon Sep 17 00:00:00 2001
From: Magnus Hagander <magnus@hagander.net>
Date: Thu, 10 Feb 2011 15:09:35 +0100
Subject: [PATCH] Track last time for statistics reset on databases and
bgwriter
Tracks one counter for each database, which is reset whenever
the statistics for any individual object inside the database is
reset, and one counter for the background writer.
Tomas Vondra, reviewed by Greg Smith
---
doc/src/sgml/monitoring.sgml | 29 +++++++++++++++++++++++++---
src/backend/catalog/system_views.sql | 6 ++++--
src/backend/postmaster/pgstat.c | 13 +++++++++++++
src/backend/utils/adt/pgstatfuncs.c | 26 +++++++++++++++++++++++++
src/include/catalog/catversion.h | 2 +-
src/include/catalog/pg_proc.h | 4 ++++
src/include/pgstat.h | 4 +++-
src/test/regress/expected/rules.out | 4 ++--
8 files changed, 79 insertions(+), 9 deletions(-)
diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index ca8342155d9..2e8427a40f1 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -267,7 +267,7 @@ postgres: <replaceable>user</> <replaceable>database</> <replaceable>host</> <re
by backends (that is, not by the background writer), how many times
those backends had to execute their own fsync calls (normally the
background writer handles those even when the backend does its own
- write), and total buffers allocated.
+ write), total buffers allocated, and time of last statistics reset.
</entry>
</row>
@@ -278,9 +278,9 @@ postgres: <replaceable>user</> <replaceable>database</> <replaceable>host</> <re
number of transactions committed and rolled back in that database,
total disk blocks read, total buffer hits (i.e., block
read requests avoided by finding the block already in buffer cache),
- number of rows returned, fetched, inserted, updated and deleted, and
+ number of rows returned, fetched, inserted, updated and deleted, the
total number of queries cancelled due to conflict with recovery (on
- standby servers).
+ standby servers), and time of last statistics reset.
</entry>
</row>
@@ -662,6 +662,19 @@ postgres: <replaceable>user</> <replaceable>database</> <replaceable>host</> <re
</entry>
</row>
+ <row>
+ <entry><literal><function>pg_stat_get_db_stat_reset_time</function>(<type>oid</type>)</literal></entry>
+ <entry><type>timestamptz</type></entry>
+ <entry>
+ Time of the last statistics reset for the database. Initialized to the
+ system time during the first connection to each database. The reset time
+ is updated when you call <function>pg_stat_reset</function> on the
+ database, as well as upon execution of
+ <function>pg_stat_reset_single_table_counters</function> against any
+ table or index in it.
+ </entry>
+ </row>
+
<row>
<entry><literal><function>pg_stat_get_numscans</function>(<type>oid</type>)</literal></entry>
<entry><type>bigint</type></entry>
@@ -1126,6 +1139,16 @@ postgres: <replaceable>user</> <replaceable>database</> <replaceable>host</> <re
</entry>
</row>
+ <row>
+ <entry><literal><function>pg_stat_get_bgwriter_stat_reset_time()</function></literal></entry>
+ <entry><type>timestamptz</type></entry>
+ <entry>
+ Time of the last statistics reset for the background writer, updated
+ when executing <function>pg_stat_reset_shared('bgwriter')</function>
+ on the database cluster.
+ </entry>
+ </row>
+
<row>
<entry><literal><function>pg_stat_get_buf_written_backend()</function></literal></entry>
<entry><type>bigint</type></entry>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 987026c8358..e1d91afbd36 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -530,7 +530,8 @@ CREATE VIEW pg_stat_database AS
pg_stat_get_db_tuples_inserted(D.oid) AS tup_inserted,
pg_stat_get_db_tuples_updated(D.oid) AS tup_updated,
pg_stat_get_db_tuples_deleted(D.oid) AS tup_deleted,
- pg_stat_get_db_conflict_all(D.oid) AS conflicts
+ pg_stat_get_db_conflict_all(D.oid) AS conflicts,
+ pg_stat_get_db_stat_reset_time(D.oid) AS stats_reset
FROM pg_database D;
CREATE VIEW pg_stat_database_conflicts AS
@@ -577,7 +578,8 @@ CREATE VIEW pg_stat_bgwriter AS
pg_stat_get_bgwriter_maxwritten_clean() AS maxwritten_clean,
pg_stat_get_buf_written_backend() AS buffers_backend,
pg_stat_get_buf_fsync_backend() AS buffers_backend_fsync,
- pg_stat_get_buf_alloc() AS buffers_alloc;
+ pg_stat_get_buf_alloc() AS buffers_alloc,
+ pg_stat_get_bgwriter_stat_reset_time() AS stats_reset;
CREATE VIEW pg_user_mappings AS
SELECT
diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index 301568f6df3..b391b48153e 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -3160,6 +3160,8 @@ pgstat_get_db_entry(Oid databaseid, bool create)
result->n_conflict_bufferpin = 0;
result->n_conflict_startup_deadlock = 0;
+ result->stat_reset_timestamp = GetCurrentTimestamp();
+
memset(&hash_ctl, 0, sizeof(hash_ctl));
hash_ctl.keysize = sizeof(Oid);
hash_ctl.entrysize = sizeof(PgStat_StatTabEntry);
@@ -3439,6 +3441,12 @@ pgstat_read_statsfile(Oid onlydb, bool permanent)
*/
memset(&globalStats, 0, sizeof(globalStats));
+ /*
+ * Set the current timestamp (will be kept only in case we can't load an
+ * existing statsfile.
+ */
+ globalStats.stat_reset_timestamp = GetCurrentTimestamp();
+
/*
* Try to open the status file. If it doesn't exist, the backends simply
* return zero for anything and the collector simply starts from scratch
@@ -4052,6 +4060,8 @@ pgstat_recv_resetcounter(PgStat_MsgResetcounter *msg, int len)
dbentry->n_tuples_deleted = 0;
dbentry->last_autovac_time = 0;
+ dbentry->stat_reset_timestamp = GetCurrentTimestamp();
+
memset(&hash_ctl, 0, sizeof(hash_ctl));
hash_ctl.keysize = sizeof(Oid);
hash_ctl.entrysize = sizeof(PgStat_StatTabEntry);
@@ -4083,6 +4093,7 @@ pgstat_recv_resetsharedcounter(PgStat_MsgResetsharedcounter *msg, int len)
{
/* Reset the global background writer statistics for the cluster. */
memset(&globalStats, 0, sizeof(globalStats));
+ globalStats.stat_reset_timestamp = GetCurrentTimestamp();
}
/*
@@ -4107,6 +4118,8 @@ pgstat_recv_resetsinglecounter(PgStat_MsgResetsinglecounter *msg, int len)
if (!dbentry)
return;
+ /* Set the reset timestamp for the whole database */
+ dbentry->stat_reset_timestamp = GetCurrentTimestamp();
/* Remove object if it exists, ignore it if not */
if (msg->m_resettype == RESET_TABLE)
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index a95ba8b3eb3..f8f99615143 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -77,12 +77,14 @@ extern Datum pg_stat_get_db_conflict_snapshot(PG_FUNCTION_ARGS);
extern Datum pg_stat_get_db_conflict_bufferpin(PG_FUNCTION_ARGS);
extern Datum pg_stat_get_db_conflict_startup_deadlock(PG_FUNCTION_ARGS);
extern Datum pg_stat_get_db_conflict_all(PG_FUNCTION_ARGS);
+extern Datum pg_stat_get_db_stat_reset_time(PG_FUNCTION_ARGS);
extern Datum pg_stat_get_bgwriter_timed_checkpoints(PG_FUNCTION_ARGS);
extern Datum pg_stat_get_bgwriter_requested_checkpoints(PG_FUNCTION_ARGS);
extern Datum pg_stat_get_bgwriter_buf_written_checkpoints(PG_FUNCTION_ARGS);
extern Datum pg_stat_get_bgwriter_buf_written_clean(PG_FUNCTION_ARGS);
extern Datum pg_stat_get_bgwriter_maxwritten_clean(PG_FUNCTION_ARGS);
+extern Datum pg_stat_get_bgwriter_stat_reset_time(PG_FUNCTION_ARGS);
extern Datum pg_stat_get_buf_written_backend(PG_FUNCTION_ARGS);
extern Datum pg_stat_get_buf_fsync_backend(PG_FUNCTION_ARGS);
extern Datum pg_stat_get_buf_alloc(PG_FUNCTION_ARGS);
@@ -1135,6 +1137,24 @@ pg_stat_get_db_tuples_deleted(PG_FUNCTION_ARGS)
PG_RETURN_INT64(result);
}
+Datum
+pg_stat_get_db_stat_reset_time(PG_FUNCTION_ARGS)
+{
+ Oid dbid = PG_GETARG_OID(0);
+ TimestampTz result;
+ PgStat_StatDBEntry *dbentry;
+
+ if ((dbentry = pgstat_fetch_stat_dbentry(dbid)) == NULL)
+ result = 0;
+ else
+ result = dbentry->stat_reset_timestamp;
+
+ if (result == 0)
+ PG_RETURN_NULL();
+ else
+ PG_RETURN_TIMESTAMPTZ(result);
+}
+
Datum
pg_stat_get_db_conflict_tablespace(PG_FUNCTION_ARGS)
{
@@ -1260,6 +1280,12 @@ pg_stat_get_bgwriter_maxwritten_clean(PG_FUNCTION_ARGS)
PG_RETURN_INT64(pgstat_fetch_global()->maxwritten_clean);
}
+Datum
+pg_stat_get_bgwriter_stat_reset_time(PG_FUNCTION_ARGS)
+{
+ PG_RETURN_TIMESTAMPTZ(pgstat_fetch_global()->stat_reset_timestamp);
+}
+
Datum
pg_stat_get_buf_written_backend(PG_FUNCTION_ARGS)
{
diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index 18739adb391..aa40e221021 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -53,6 +53,6 @@
*/
/* yyyymmddN */
-#define CATALOG_VERSION_NO 201102091
+#define CATALOG_VERSION_NO 201102101
#endif
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 9e6ec3dda50..01b002a1454 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -3131,6 +3131,8 @@ DATA(insert OID = 3069 ( pg_stat_get_db_conflict_startup_deadlock PGNSP PGUID 1
DESCR("statistics: recovery conflicts in database caused by buffer deadlock");
DATA(insert OID = 3070 ( pg_stat_get_db_conflict_all PGNSP PGUID 12 1 0 0 f f f t f s 1 0 20 "26" _null_ _null_ _null_ _null_ pg_stat_get_db_conflict_all _null_ _null_ _null_ ));
DESCR("statistics: recovery conflicts in database");
+DATA(insert OID = 3074 ( pg_stat_get_db_stat_reset_time PGNSP PGUID 12 1 0 0 f f f t f s 1 0 1184 "26" _null_ _null_ _null_ _null_ pg_stat_get_db_stat_reset_time _null_ _null_ _null_ ));
+DESCR("statistics: last reset for a database");
DATA(insert OID = 2769 ( pg_stat_get_bgwriter_timed_checkpoints PGNSP PGUID 12 1 0 0 f f f t f s 0 0 20 "" _null_ _null_ _null_ _null_ pg_stat_get_bgwriter_timed_checkpoints _null_ _null_ _null_ ));
DESCR("statistics: number of timed checkpoints started by the bgwriter");
DATA(insert OID = 2770 ( pg_stat_get_bgwriter_requested_checkpoints PGNSP PGUID 12 1 0 0 f f f t f s 0 0 20 "" _null_ _null_ _null_ _null_ pg_stat_get_bgwriter_requested_checkpoints _null_ _null_ _null_ ));
@@ -3141,6 +3143,8 @@ DATA(insert OID = 2772 ( pg_stat_get_bgwriter_buf_written_clean PGNSP PGUID 12 1
DESCR("statistics: number of buffers written by the bgwriter for cleaning dirty buffers");
DATA(insert OID = 2773 ( pg_stat_get_bgwriter_maxwritten_clean PGNSP PGUID 12 1 0 0 f f f t f s 0 0 20 "" _null_ _null_ _null_ _null_ pg_stat_get_bgwriter_maxwritten_clean _null_ _null_ _null_ ));
DESCR("statistics: number of times the bgwriter stopped processing when it had written too many buffers while cleaning");
+DATA(insert OID = 3075 ( pg_stat_get_bgwriter_stat_reset_time PGNSP PGUID 12 1 0 0 f f f t f s 0 0 1184 "" _null_ _null_ _null_ _null_ pg_stat_get_bgwriter_stat_reset_time _null_ _null_ _null_ ));
+DESCR("statistics: last reset for the bgwriter");
DATA(insert OID = 2775 ( pg_stat_get_buf_written_backend PGNSP PGUID 12 1 0 0 f f f t f s 0 0 20 "" _null_ _null_ _null_ _null_ pg_stat_get_buf_written_backend _null_ _null_ _null_ ));
DESCR("statistics: number of buffers written by backends");
DATA(insert OID = 3063 ( pg_stat_get_buf_fsync_backend PGNSP PGUID 12 1 0 0 f f f t f s 0 0 20 "" _null_ _null_ _null_ _null_ pg_stat_get_buf_fsync_backend _null_ _null_ _null_ ));
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index 9f4e0cac9b8..0414b19868e 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -484,7 +484,7 @@ typedef union PgStat_Msg
* ------------------------------------------------------------
*/
-#define PGSTAT_FILE_FORMAT_ID 0x01A5BC98
+#define PGSTAT_FILE_FORMAT_ID 0x01A5BC99
/* ----------
* PgStat_StatDBEntry The collector's data per database
@@ -508,6 +508,7 @@ typedef struct PgStat_StatDBEntry
PgStat_Counter n_conflict_snapshot;
PgStat_Counter n_conflict_bufferpin;
PgStat_Counter n_conflict_startup_deadlock;
+ TimestampTz stat_reset_timestamp;
/*
@@ -584,6 +585,7 @@ typedef struct PgStat_GlobalStats
PgStat_Counter buf_written_backend;
PgStat_Counter buf_fsync_backend;
PgStat_Counter buf_alloc;
+ TimestampTz stat_reset_timestamp;
} PgStat_GlobalStats;
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 8ddc116d665..b49467870ef 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1294,8 +1294,8 @@ SELECT viewname, definition FROM pg_views WHERE schemaname <> 'information_schem
pg_stat_activity | SELECT s.datid, d.datname, s.procpid, s.usesysid, u.rolname AS usename, s.application_name, s.client_addr, s.client_port, s.backend_start, s.xact_start, s.query_start, s.waiting, s.current_query FROM pg_database d, pg_stat_get_activity(NULL::integer) s(datid, procpid, usesysid, application_name, current_query, waiting, xact_start, query_start, backend_start, client_addr, client_port), pg_authid u WHERE ((s.datid = d.oid) AND (s.usesysid = u.oid));
pg_stat_all_indexes | SELECT c.oid AS relid, i.oid AS indexrelid, n.nspname AS schemaname, c.relname, i.relname AS indexrelname, pg_stat_get_numscans(i.oid) AS idx_scan, pg_stat_get_tuples_returned(i.oid) AS idx_tup_read, pg_stat_get_tuples_fetched(i.oid) AS idx_tup_fetch FROM (((pg_class c JOIN pg_index x ON ((c.oid = x.indrelid))) JOIN pg_class i ON ((i.oid = x.indexrelid))) LEFT JOIN pg_namespace n ON ((n.oid = c.relnamespace))) WHERE (c.relkind = ANY (ARRAY['r'::"char", 't'::"char"]));
pg_stat_all_tables | SELECT c.oid AS relid, n.nspname AS schemaname, c.relname, pg_stat_get_numscans(c.oid) AS seq_scan, pg_stat_get_tuples_returned(c.oid) AS seq_tup_read, (sum(pg_stat_get_numscans(i.indexrelid)))::bigint AS idx_scan, ((sum(pg_stat_get_tuples_fetched(i.indexrelid)))::bigint + pg_stat_get_tuples_fetched(c.oid)) AS idx_tup_fetch, pg_stat_get_tuples_inserted(c.oid) AS n_tup_ins, pg_stat_get_tuples_updated(c.oid) AS n_tup_upd, pg_stat_get_tuples_deleted(c.oid) AS n_tup_del, pg_stat_get_tuples_hot_updated(c.oid) AS n_tup_hot_upd, pg_stat_get_live_tuples(c.oid) AS n_live_tup, pg_stat_get_dead_tuples(c.oid) AS n_dead_tup, pg_stat_get_last_vacuum_time(c.oid) AS last_vacuum, pg_stat_get_last_autovacuum_time(c.oid) AS last_autovacuum, pg_stat_get_last_analyze_time(c.oid) AS last_analyze, pg_stat_get_last_autoanalyze_time(c.oid) AS last_autoanalyze, pg_stat_get_vacuum_count(c.oid) AS vacuum_count, pg_stat_get_autovacuum_count(c.oid) AS autovacuum_count, pg_stat_get_analyze_count(c.oid) AS analyze_count, pg_stat_get_autoanalyze_count(c.oid) AS autoanalyze_count FROM ((pg_class c LEFT JOIN pg_index i ON ((c.oid = i.indrelid))) LEFT JOIN pg_namespace n ON ((n.oid = c.relnamespace))) WHERE (c.relkind = ANY (ARRAY['r'::"char", 't'::"char"])) GROUP BY c.oid, n.nspname, c.relname;
- pg_stat_bgwriter | SELECT pg_stat_get_bgwriter_timed_checkpoints() AS checkpoints_timed, pg_stat_get_bgwriter_requested_checkpoints() AS checkpoints_req, pg_stat_get_bgwriter_buf_written_checkpoints() AS buffers_checkpoint, pg_stat_get_bgwriter_buf_written_clean() AS buffers_clean, pg_stat_get_bgwriter_maxwritten_clean() AS maxwritten_clean, pg_stat_get_buf_written_backend() AS buffers_backend, pg_stat_get_buf_fsync_backend() AS buffers_backend_fsync, pg_stat_get_buf_alloc() AS buffers_alloc;
- pg_stat_database | SELECT d.oid AS datid, d.datname, pg_stat_get_db_numbackends(d.oid) AS numbackends, pg_stat_get_db_xact_commit(d.oid) AS xact_commit, pg_stat_get_db_xact_rollback(d.oid) AS xact_rollback, (pg_stat_get_db_blocks_fetched(d.oid) - pg_stat_get_db_blocks_hit(d.oid)) AS blks_read, pg_stat_get_db_blocks_hit(d.oid) AS blks_hit, pg_stat_get_db_tuples_returned(d.oid) AS tup_returned, pg_stat_get_db_tuples_fetched(d.oid) AS tup_fetched, pg_stat_get_db_tuples_inserted(d.oid) AS tup_inserted, pg_stat_get_db_tuples_updated(d.oid) AS tup_updated, pg_stat_get_db_tuples_deleted(d.oid) AS tup_deleted, pg_stat_get_db_conflict_all(d.oid) AS conflicts FROM pg_database d;
+ pg_stat_bgwriter | SELECT pg_stat_get_bgwriter_timed_checkpoints() AS checkpoints_timed, pg_stat_get_bgwriter_requested_checkpoints() AS checkpoints_req, pg_stat_get_bgwriter_buf_written_checkpoints() AS buffers_checkpoint, pg_stat_get_bgwriter_buf_written_clean() AS buffers_clean, pg_stat_get_bgwriter_maxwritten_clean() AS maxwritten_clean, pg_stat_get_buf_written_backend() AS buffers_backend, pg_stat_get_buf_fsync_backend() AS buffers_backend_fsync, pg_stat_get_buf_alloc() AS buffers_alloc, pg_stat_get_bgwriter_stat_reset_time() AS stats_reset;
+ pg_stat_database | SELECT d.oid AS datid, d.datname, pg_stat_get_db_numbackends(d.oid) AS numbackends, pg_stat_get_db_xact_commit(d.oid) AS xact_commit, pg_stat_get_db_xact_rollback(d.oid) AS xact_rollback, (pg_stat_get_db_blocks_fetched(d.oid) - pg_stat_get_db_blocks_hit(d.oid)) AS blks_read, pg_stat_get_db_blocks_hit(d.oid) AS blks_hit, pg_stat_get_db_tuples_returned(d.oid) AS tup_returned, pg_stat_get_db_tuples_fetched(d.oid) AS tup_fetched, pg_stat_get_db_tuples_inserted(d.oid) AS tup_inserted, pg_stat_get_db_tuples_updated(d.oid) AS tup_updated, pg_stat_get_db_tuples_deleted(d.oid) AS tup_deleted, pg_stat_get_db_conflict_all(d.oid) AS conflicts, pg_stat_get_db_stat_reset_time(d.oid) AS stats_reset FROM pg_database d;
pg_stat_database_conflicts | SELECT d.oid AS datid, d.datname, pg_stat_get_db_conflict_tablespace(d.oid) AS confl_tablespace, pg_stat_get_db_conflict_lock(d.oid) AS confl_lock, pg_stat_get_db_conflict_snapshot(d.oid) AS confl_snapshot, pg_stat_get_db_conflict_bufferpin(d.oid) AS confl_bufferpin, pg_stat_get_db_conflict_startup_deadlock(d.oid) AS confl_deadlock FROM pg_database d;
pg_stat_replication | SELECT s.procpid, s.usesysid, u.rolname AS usename, s.application_name, s.client_addr, s.client_port, s.backend_start, w.state, w.sent_location FROM pg_stat_get_activity(NULL::integer) s(datid, procpid, usesysid, application_name, current_query, waiting, xact_start, query_start, backend_start, client_addr, client_port), pg_authid u, pg_stat_get_wal_senders() w(procpid, state, sent_location) WHERE ((s.usesysid = u.oid) AND (s.procpid = w.procpid));
pg_stat_sys_indexes | SELECT pg_stat_all_indexes.relid, pg_stat_all_indexes.indexrelid, pg_stat_all_indexes.schemaname, pg_stat_all_indexes.relname, pg_stat_all_indexes.indexrelname, pg_stat_all_indexes.idx_scan, pg_stat_all_indexes.idx_tup_read, pg_stat_all_indexes.idx_tup_fetch FROM pg_stat_all_indexes WHERE ((pg_stat_all_indexes.schemaname = ANY (ARRAY['pg_catalog'::name, 'information_schema'::name])) OR (pg_stat_all_indexes.schemaname ~ '^pg_toast'::text));
--
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