From 97aed1483d21359d0c0dfd1c332c0e569f66ac09 Mon Sep 17 00:00:00 2001 From: Pavlo Golub Date: Wed, 10 Dec 2025 15:14:22 +0000 Subject: [PATCH] Add last_executed timestamp to pg_stat_statements This patch adds a last_executed timestamp column to pg_stat_statements, recording when each statement was most recently executed. This enables efficient filtering of active statements, which is particularly useful for monitoring systems that poll pg_stat_statements periodically. The new column helps reduce storage overhead in monitoring systems. For example, a system polling every 3 minutes can now filter statements executed since the last poll, avoiding storage of unchanged statistics. The implementation updates the timestamp on every statement execution with minimal overhead, protected by the existing spinlock. The timestamp is persisted with other statistics and survives server restarts. Changes include: - New last_executed column of type timestamptz in pg_stat_statements view - pg_stat_statements_1_14 function for version 1.14 - Upgrade script from version 1.13 to 1.14 - Regression test covering timestamp behavior - Updated file header magic number for stats file format change - Documentation updates --- contrib/pg_stat_statements/Makefile | 3 +- .../expected/last_executed.out | 113 ++++++++++++++++++ contrib/pg_stat_statements/meson.build | 2 + .../pg_stat_statements--1.13--1.14.sql | 79 ++++++++++++ .../pg_stat_statements/pg_stat_statements.c | 30 ++++- .../pg_stat_statements.control | 2 +- .../pg_stat_statements/sql/last_executed.sql | 52 ++++++++ doc/src/sgml/pgstatstatements.sgml | 9 ++ 8 files changed, 286 insertions(+), 4 deletions(-) create mode 100644 contrib/pg_stat_statements/expected/last_executed.out create mode 100644 contrib/pg_stat_statements/pg_stat_statements--1.13--1.14.sql create mode 100644 contrib/pg_stat_statements/sql/last_executed.sql diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile index fe0478ac552..518030d2188 100644 --- a/contrib/pg_stat_statements/Makefile +++ b/contrib/pg_stat_statements/Makefile @@ -7,6 +7,7 @@ OBJS = \ EXTENSION = pg_stat_statements DATA = pg_stat_statements--1.4.sql \ + pg_stat_statements--1.13--1.14.sql \ pg_stat_statements--1.12--1.13.sql \ pg_stat_statements--1.11--1.12.sql pg_stat_statements--1.10--1.11.sql \ pg_stat_statements--1.9--1.10.sql pg_stat_statements--1.8--1.9.sql \ @@ -21,7 +22,7 @@ LDFLAGS_SL += $(filter -lm, $(LIBS)) REGRESS_OPTS = --temp-config $(top_srcdir)/contrib/pg_stat_statements/pg_stat_statements.conf REGRESS = select dml cursors utility level_tracking planning \ user_activity wal entry_timestamp privileges extended \ - parallel plancache cleanup oldextversions squashing + parallel plancache cleanup oldextversions squashing last_executed # Disabled because these tests require "shared_preload_libraries=pg_stat_statements", # which typical installcheck users do not have (e.g. buildfarm clients). NO_INSTALLCHECK = 1 diff --git a/contrib/pg_stat_statements/expected/last_executed.out b/contrib/pg_stat_statements/expected/last_executed.out new file mode 100644 index 00000000000..9d6502566b1 --- /dev/null +++ b/contrib/pg_stat_statements/expected/last_executed.out @@ -0,0 +1,113 @@ +-- +-- last_executed timestamp +-- +SELECT pg_stat_statements_reset() IS NOT NULL AS t; + t +--- + t +(1 row) + +SELECT 1 AS "LAST1"; + LAST1 +------- + 1 +(1 row) + +SELECT now() AS ref_ts1 \gset +SELECT pg_sleep(0.1); + pg_sleep +---------- + +(1 row) + +SELECT 2 AS "LAST2"; + LAST2 +------- + 2 +(1 row) + +SELECT now() AS ref_ts2 \gset +-- verify last_executed is set and updated +SELECT + query, + last_executed IS NOT NULL as has_ts, + last_executed >= :'ref_ts1' as after_ref1, + stats_since <= last_executed as after_stats_since +FROM pg_stat_statements +WHERE query LIKE '%LAST%' +ORDER BY query COLLATE "C"; + query | has_ts | after_ref1 | after_stats_since +----------------------+--------+------------+------------------- + SELECT $1 AS "LAST1" | t | t | t +(1 row) + +-- execute again and verify update +SELECT pg_sleep(0.1); + pg_sleep +---------- + +(1 row) + +SELECT 1 AS "LAST1"; + LAST1 +------- + 1 +(1 row) + +SELECT now() AS ref_ts3 \gset +SELECT + query, + last_executed >= :'ref_ts3' as updated +FROM pg_stat_statements +WHERE query LIKE '%LAST1%'; + query | updated +----------------------+--------- + SELECT $1 AS "LAST1" | f +(1 row) + +-- test filtering (monitoring use case) +SELECT query, count(*) as count +FROM pg_stat_statements +WHERE last_executed >= :'ref_ts2' +GROUP BY query +ORDER BY query COLLATE "C"; + query | count +-------------------------------------------------------+------- + SELECT +| 1 + query, +| + last_executed >= $1 as updated +| + FROM pg_stat_statements +| + WHERE query LIKE $2 | + SELECT +| 1 + query, +| + last_executed IS NOT NULL as has_ts, +| + last_executed >= $1 as after_ref1, +| + stats_since <= last_executed as after_stats_since+| + FROM pg_stat_statements +| + WHERE query LIKE $2 +| + ORDER BY query COLLATE "C" | + SELECT $1 AS "LAST1" | 1 + SELECT now() AS ref_ts1 | 1 + SELECT pg_sleep($1) | 1 +(5 rows) + +-- minmax reset should not affect last_executed +SELECT pg_stat_statements_reset(0, 0, queryid, true) +FROM pg_stat_statements +WHERE query LIKE '%LAST1%' \gset +SELECT + query, + last_executed >= :'ref_ts3' as ts_preserved +FROM pg_stat_statements +WHERE query LIKE '%LAST1%'; + query | ts_preserved +----------------------+-------------- + SELECT $1 AS "LAST1" | f +(1 row) + +SELECT pg_stat_statements_reset() IS NOT NULL AS t; + t +--- + t +(1 row) + diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build index 7b8bfbb1de7..12760f9c3a1 100644 --- a/contrib/pg_stat_statements/meson.build +++ b/contrib/pg_stat_statements/meson.build @@ -21,6 +21,7 @@ contrib_targets += pg_stat_statements install_data( 'pg_stat_statements.control', 'pg_stat_statements--1.4.sql', + 'pg_stat_statements--1.13--1.14.sql', 'pg_stat_statements--1.12--1.13.sql', 'pg_stat_statements--1.11--1.12.sql', 'pg_stat_statements--1.10--1.11.sql', @@ -59,6 +60,7 @@ tests += { 'cleanup', 'oldextversions', 'squashing', + 'last_executed', ], 'regress_args': ['--temp-config', files('pg_stat_statements.conf')], # Disabled because these tests require diff --git a/contrib/pg_stat_statements/pg_stat_statements--1.13--1.14.sql b/contrib/pg_stat_statements/pg_stat_statements--1.13--1.14.sql new file mode 100644 index 00000000000..5b9ca8b2f77 --- /dev/null +++ b/contrib/pg_stat_statements/pg_stat_statements--1.13--1.14.sql @@ -0,0 +1,79 @@ +/* contrib/pg_stat_statements/pg_stat_statements--1.13--1.14.sql */ + +-- complain if script is sourced in psql, rather than via ALTER EXTENSION +\echo Use "ALTER EXTENSION pg_stat_statements UPDATE TO '1.14'" to load this file. \quit + +/* First we have to remove them from the extension */ +ALTER EXTENSION pg_stat_statements DROP VIEW pg_stat_statements; +ALTER EXTENSION pg_stat_statements DROP FUNCTION pg_stat_statements(boolean); + +/* Then we can drop them */ +DROP VIEW pg_stat_statements; +DROP FUNCTION pg_stat_statements(boolean); + +/* Now redefine */ +CREATE FUNCTION pg_stat_statements(IN showtext boolean, + OUT userid oid, + OUT dbid oid, + OUT toplevel bool, + OUT queryid bigint, + OUT query text, + OUT plans int8, + OUT total_plan_time float8, + OUT min_plan_time float8, + OUT max_plan_time float8, + OUT mean_plan_time float8, + OUT stddev_plan_time float8, + OUT calls int8, + OUT total_exec_time float8, + OUT min_exec_time float8, + OUT max_exec_time float8, + OUT mean_exec_time float8, + OUT stddev_exec_time float8, + OUT rows int8, + OUT shared_blks_hit int8, + OUT shared_blks_read int8, + OUT shared_blks_dirtied int8, + OUT shared_blks_written int8, + OUT local_blks_hit int8, + OUT local_blks_read int8, + OUT local_blks_dirtied int8, + OUT local_blks_written int8, + OUT temp_blks_read int8, + OUT temp_blks_written int8, + OUT shared_blk_read_time float8, + OUT shared_blk_write_time float8, + OUT local_blk_read_time float8, + OUT local_blk_write_time float8, + OUT temp_blk_read_time float8, + OUT temp_blk_write_time float8, + OUT wal_records int8, + OUT wal_fpi int8, + OUT wal_bytes numeric, + OUT wal_buffers_full int8, + OUT jit_functions int8, + OUT jit_generation_time float8, + OUT jit_inlining_count int8, + OUT jit_inlining_time float8, + OUT jit_optimization_count int8, + OUT jit_optimization_time float8, + OUT jit_emission_count int8, + OUT jit_emission_time float8, + OUT jit_deform_count int8, + OUT jit_deform_time float8, + OUT parallel_workers_to_launch int8, + OUT parallel_workers_launched int8, + OUT generic_plan_calls int8, + OUT custom_plan_calls int8, + OUT stats_since timestamp with time zone, + OUT minmax_stats_since timestamp with time zone, + OUT last_executed timestamp with time zone +) +RETURNS SETOF record +AS 'MODULE_PATHNAME', 'pg_stat_statements_1_14' +LANGUAGE C STRICT VOLATILE PARALLEL SAFE; + +CREATE VIEW pg_stat_statements AS + SELECT * FROM pg_stat_statements(true); + +GRANT SELECT ON pg_stat_statements TO PUBLIC; diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c index 39208f80b5b..df5890e3fec 100644 --- a/contrib/pg_stat_statements/pg_stat_statements.c +++ b/contrib/pg_stat_statements/pg_stat_statements.c @@ -86,7 +86,7 @@ PG_MODULE_MAGIC_EXT( #define PGSS_TEXT_FILE PG_STAT_TMP_DIR "/pgss_query_texts.stat" /* Magic number identifying the stats file format */ -static const uint32 PGSS_FILE_HEADER = 0x20250731; +static const uint32 PGSS_FILE_HEADER = 0x20251210; /* PostgreSQL major version number, changes in which invalidate all entries */ static const uint32 PGSS_PG_MAJOR_VERSION = PG_VERSION_NUM / 100; @@ -116,6 +116,7 @@ typedef enum pgssVersion PGSS_V1_11, PGSS_V1_12, PGSS_V1_13, + PGSS_V1_14, } pgssVersion; typedef enum pgssStoreKind @@ -213,6 +214,7 @@ typedef struct Counters * launched */ int64 generic_plan_calls; /* number of calls using a generic plan */ int64 custom_plan_calls; /* number of calls using a custom plan */ + TimestampTz last_executed; /* timestamp of last statement execution */ } Counters; /* @@ -327,6 +329,7 @@ PG_FUNCTION_INFO_V1(pg_stat_statements_1_10); PG_FUNCTION_INFO_V1(pg_stat_statements_1_11); PG_FUNCTION_INFO_V1(pg_stat_statements_1_12); PG_FUNCTION_INFO_V1(pg_stat_statements_1_13); +PG_FUNCTION_INFO_V1(pg_stat_statements_1_14); PG_FUNCTION_INFO_V1(pg_stat_statements); PG_FUNCTION_INFO_V1(pg_stat_statements_info); @@ -1513,6 +1516,9 @@ pgss_store(const char *query, int64 queryId, else if (planOrigin == PLAN_STMT_CACHE_CUSTOM) entry->counters.custom_plan_calls++; + /* Update last_executed timestamp */ + entry->counters.last_executed = GetCurrentTimestamp(); + SpinLockRelease(&entry->mutex); } @@ -1581,7 +1587,8 @@ pg_stat_statements_reset(PG_FUNCTION_ARGS) #define PG_STAT_STATEMENTS_COLS_V1_11 49 #define PG_STAT_STATEMENTS_COLS_V1_12 52 #define PG_STAT_STATEMENTS_COLS_V1_13 54 -#define PG_STAT_STATEMENTS_COLS 54 /* maximum of above */ +#define PG_STAT_STATEMENTS_COLS_V1_14 55 +#define PG_STAT_STATEMENTS_COLS 55 /* maximum of above */ /* * Retrieve statement statistics. @@ -1593,6 +1600,16 @@ pg_stat_statements_reset(PG_FUNCTION_ARGS) * expected API version is identified by embedding it in the C name of the * function. Unfortunately we weren't bright enough to do that for 1.1. */ +Datum +pg_stat_statements_1_14(PG_FUNCTION_ARGS) +{ + bool showtext = PG_GETARG_BOOL(0); + + pg_stat_statements_internal(fcinfo, PGSS_V1_14, showtext); + + return (Datum) 0; +} + Datum pg_stat_statements_1_13(PG_FUNCTION_ARGS) { @@ -1765,6 +1782,10 @@ pg_stat_statements_internal(FunctionCallInfo fcinfo, if (api_version != PGSS_V1_13) elog(ERROR, "incorrect number of output arguments"); break; + case PG_STAT_STATEMENTS_COLS_V1_14: + if (api_version != PGSS_V1_14) + elog(ERROR, "incorrect number of output arguments"); + break; default: elog(ERROR, "incorrect number of output arguments"); } @@ -2027,6 +2048,10 @@ pg_stat_statements_internal(FunctionCallInfo fcinfo, values[i++] = TimestampTzGetDatum(stats_since); values[i++] = TimestampTzGetDatum(minmax_stats_since); } + if (api_version >= PGSS_V1_14) + { + values[i++] = TimestampTzGetDatum(tmp.last_executed); + } Assert(i == (api_version == PGSS_V1_0 ? PG_STAT_STATEMENTS_COLS_V1_0 : api_version == PGSS_V1_1 ? PG_STAT_STATEMENTS_COLS_V1_1 : @@ -2038,6 +2063,7 @@ pg_stat_statements_internal(FunctionCallInfo fcinfo, api_version == PGSS_V1_11 ? PG_STAT_STATEMENTS_COLS_V1_11 : api_version == PGSS_V1_12 ? PG_STAT_STATEMENTS_COLS_V1_12 : api_version == PGSS_V1_13 ? PG_STAT_STATEMENTS_COLS_V1_13 : + api_version == PGSS_V1_14 ? PG_STAT_STATEMENTS_COLS_V1_14 : -1 /* fail if you forget to update this assert */ )); tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls); diff --git a/contrib/pg_stat_statements/pg_stat_statements.control b/contrib/pg_stat_statements/pg_stat_statements.control index 2eee0ceffa8..61ae41efc14 100644 --- a/contrib/pg_stat_statements/pg_stat_statements.control +++ b/contrib/pg_stat_statements/pg_stat_statements.control @@ -1,5 +1,5 @@ # pg_stat_statements extension comment = 'track planning and execution statistics of all SQL statements executed' -default_version = '1.13' +default_version = '1.14' module_pathname = '$libdir/pg_stat_statements' relocatable = true diff --git a/contrib/pg_stat_statements/sql/last_executed.sql b/contrib/pg_stat_statements/sql/last_executed.sql new file mode 100644 index 00000000000..b68ec2165be --- /dev/null +++ b/contrib/pg_stat_statements/sql/last_executed.sql @@ -0,0 +1,52 @@ +-- +-- last_executed timestamp +-- + +SELECT pg_stat_statements_reset() IS NOT NULL AS t; + +SELECT 1 AS "LAST1"; +SELECT now() AS ref_ts1 \gset +SELECT pg_sleep(0.1); +SELECT 2 AS "LAST2"; +SELECT now() AS ref_ts2 \gset + +-- verify last_executed is set and updated +SELECT + query, + last_executed IS NOT NULL as has_ts, + last_executed >= :'ref_ts1' as after_ref1, + stats_since <= last_executed as after_stats_since +FROM pg_stat_statements +WHERE query LIKE '%LAST%' +ORDER BY query COLLATE "C"; + +-- execute again and verify update +SELECT pg_sleep(0.1); +SELECT 1 AS "LAST1"; +SELECT now() AS ref_ts3 \gset + +SELECT + query, + last_executed >= :'ref_ts3' as updated +FROM pg_stat_statements +WHERE query LIKE '%LAST1%'; + +-- test filtering (monitoring use case) +SELECT query, count(*) as count +FROM pg_stat_statements +WHERE last_executed >= :'ref_ts2' +GROUP BY query +ORDER BY query COLLATE "C"; + +-- minmax reset should not affect last_executed +SELECT pg_stat_statements_reset(0, 0, queryid, true) +FROM pg_stat_statements +WHERE query LIKE '%LAST1%' \gset + +SELECT + query, + last_executed >= :'ref_ts3' as ts_preserved +FROM pg_stat_statements +WHERE query LIKE '%LAST1%'; + +SELECT pg_stat_statements_reset() IS NOT NULL AS t; diff --git a/doc/src/sgml/pgstatstatements.sgml b/doc/src/sgml/pgstatstatements.sgml index d753de5836e..e5d75c6a2f5 100644 --- a/doc/src/sgml/pgstatstatements.sgml +++ b/doc/src/sgml/pgstatstatements.sgml @@ -593,6 +593,15 @@ max_exec_time) + + + + last_executed timestamp with time zone + + + Time at which the statement was last executed + + -- 2.52.0