From ac51b84c6e262e7433bca36b2d40319bdad30aa2 Mon Sep 17 00:00:00 2001 From: Andrei Zubkov Date: Fri, 17 Nov 2023 11:35:25 +0300 Subject: [PATCH 2/2] Track statement entry timestamp in contrib/pg_stat_statements This patch adds 'stats_since' and 'minmax_stats_since' columns to the pg_stat_statements view and pg_stat_statements() function. The new min/max reset mode for the pg_stat_stetments_reset() function is controlled by the parameter minmax_only. 'stat_since' column is populated with the current timestamp when a new statement is added to the pg_stat_statements hashtable. It provides clean information about statistics collection time intervals for each statement. Besides it can be used by sampling solutions to detect situations when a statement was evicted and stored again between samples. Such a sampling solution could derive any pg_stat_statements statistic values for an interval between two samples with the exception of all min/max statistics. To address this issue this patch adds the ability to reset min/max statistics independently of the statement reset using the new minmax_only parameter of the pg_stat_statements_reset(userid oid, dbid oid, queryid bigint, minmax_only boolean) function. The timestamp of such reset is stored in the minmax_stats_since field for each statement. pg_stat_statements_reset() function now returns the timestamp of a reset as the result. Discussion: https://postgr.es/m/flat/72e80e7b160a6eb189df9ef6f068cce3765d37f8.camel%40moonset.ru Author: Andrei Zubkov Reviewed-by: Julien Rouhaud, Hayato Kuroda, Yuki Seino, Chengxi Sun Reviewed-by: Anton Melnikov, Darren Rush, Michael Paquier, Sergei Kornilov Reviewed-by: Alena Rybakina, Andrei Lepikhov (lepikhov) --- contrib/pg_stat_statements/Makefile | 2 +- .../expected/entry_timestamp.out | 159 ++++++++++++++++++ .../expected/oldextversions.out | 116 +++++++------ contrib/pg_stat_statements/meson.build | 1 + .../pg_stat_statements--1.10--1.11.sql | 23 ++- .../pg_stat_statements/pg_stat_statements.c | 118 ++++++++++--- .../sql/entry_timestamp.sql | 114 +++++++++++++ .../pg_stat_statements/sql/oldextversions.sql | 4 +- doc/src/sgml/pgstatstatements.sgml | 69 +++++++- 9 files changed, 510 insertions(+), 96 deletions(-) create mode 100644 contrib/pg_stat_statements/expected/entry_timestamp.out create mode 100644 contrib/pg_stat_statements/sql/entry_timestamp.sql diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile index eba4a95d91a..aecd1d6a2a0 100644 --- a/contrib/pg_stat_statements/Makefile +++ b/contrib/pg_stat_statements/Makefile @@ -19,7 +19,7 @@ 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 cleanup oldextversions + user_activity wal entry_timestamp cleanup oldextversions # 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/entry_timestamp.out b/contrib/pg_stat_statements/expected/entry_timestamp.out new file mode 100644 index 00000000000..a10c4be6bac --- /dev/null +++ b/contrib/pg_stat_statements/expected/entry_timestamp.out @@ -0,0 +1,159 @@ +-- +-- statement timestamps +-- +-- planning time is needed during tests +SET pg_stat_statements.track_planning = TRUE; +SELECT 1 AS "STMTTS1"; + STMTTS1 +--------- + 1 +(1 row) + +SELECT now() AS ref_ts \gset +SELECT 1,2 AS "STMTTS2"; + ?column? | STMTTS2 +----------+--------- + 1 | 2 +(1 row) + +SELECT stats_since >= :'ref_ts', count(*) FROM pg_stat_statements +WHERE query LIKE '%STMTTS%' +GROUP BY stats_since >= :'ref_ts' +ORDER BY stats_since >= :'ref_ts'; + ?column? | count +----------+------- + f | 1 + t | 1 +(2 rows) + +SELECT now() AS ref_ts \gset +SELECT + count(*) as total, + count(*) FILTER ( + WHERE min_plan_time + max_plan_time = 0 + ) as minmax_plan_zero, + count(*) FILTER ( + WHERE min_exec_time + max_exec_time = 0 + ) as minmax_exec_zero, + count(*) FILTER ( + WHERE minmax_stats_since >= :'ref_ts' + ) as minmax_stats_since_after_ref, + count(*) FILTER ( + WHERE stats_since >= :'ref_ts' + ) as stats_since_after_ref +FROM pg_stat_statements +WHERE query LIKE '%STMTTS%'; + total | minmax_plan_zero | minmax_exec_zero | minmax_stats_since_after_ref | stats_since_after_ref +-------+------------------+------------------+------------------------------+----------------------- + 2 | 0 | 0 | 0 | 0 +(1 row) + +-- Perform single min/max reset +SELECT pg_stat_statements_reset(0, 0, queryid, true) AS minmax_reset_ts +FROM pg_stat_statements +WHERE query LIKE '%STMTTS1%' \gset +-- check +SELECT + count(*) as total, + count(*) FILTER ( + WHERE min_plan_time + max_plan_time = 0 + ) as minmax_plan_zero, + count(*) FILTER ( + WHERE min_exec_time + max_exec_time = 0 + ) as minmax_exec_zero, + count(*) FILTER ( + WHERE minmax_stats_since >= :'ref_ts' + ) as minmax_stats_since_after_ref, + count(*) FILTER ( + WHERE stats_since >= :'ref_ts' + ) as stats_since_after_ref +FROM pg_stat_statements +WHERE query LIKE '%STMTTS%'; + total | minmax_plan_zero | minmax_exec_zero | minmax_stats_since_after_ref | stats_since_after_ref +-------+------------------+------------------+------------------------------+----------------------- + 2 | 1 | 1 | 1 | 0 +(1 row) + +-- check minmax reset timestamps +SELECT +query, minmax_stats_since = :'minmax_reset_ts' AS reset_ts_match +FROM pg_stat_statements +WHERE query LIKE '%STMTTS%' +ORDER BY query COLLATE "C"; + query | reset_ts_match +---------------------------+---------------- + SELECT $1 AS "STMTTS1" | t + SELECT $1,$2 AS "STMTTS2" | f +(2 rows) + +-- check that minmax reset does not set stats_reset +SELECT +stats_reset = :'minmax_reset_ts' AS stats_reset_ts_match +FROM pg_stat_statements_info; + stats_reset_ts_match +---------------------- + f +(1 row) + +-- Perform common min/max reset +SELECT pg_stat_statements_reset(0, 0, 0, true) AS minmax_reset_ts \gset +-- check again +SELECT + count(*) as total, + count(*) FILTER ( + WHERE min_plan_time + max_plan_time = 0 + ) as minmax_plan_zero, + count(*) FILTER ( + WHERE min_exec_time + max_exec_time = 0 + ) as minmax_exec_zero, + count(*) FILTER ( + WHERE minmax_stats_since >= :'ref_ts' + ) as minmax_ts_after_ref, + count(*) FILTER ( + WHERE minmax_stats_since = :'minmax_reset_ts' + ) as minmax_ts_match, + count(*) FILTER ( + WHERE stats_since >= :'ref_ts' + ) as stats_since_after_ref +FROM pg_stat_statements +WHERE query LIKE '%STMTTS%'; + total | minmax_plan_zero | minmax_exec_zero | minmax_ts_after_ref | minmax_ts_match | stats_since_after_ref +-------+------------------+------------------+---------------------+-----------------+----------------------- + 2 | 2 | 2 | 2 | 2 | 0 +(1 row) + +-- Execute first query once more to check stats update +SELECT 1 AS "STMTTS1"; + STMTTS1 +--------- + 1 +(1 row) + +-- check +-- we don't check planing times here to be independent of +-- plan caching approach +SELECT + count(*) as total, + count(*) FILTER ( + WHERE min_exec_time + max_exec_time = 0 + ) as minmax_exec_zero, + count(*) FILTER ( + WHERE minmax_stats_since >= :'ref_ts' + ) as minmax_ts_after_ref, + count(*) FILTER ( + WHERE stats_since >= :'ref_ts' + ) as stats_since_after_ref +FROM pg_stat_statements +WHERE query LIKE '%STMTTS%'; + total | minmax_exec_zero | minmax_ts_after_ref | stats_since_after_ref +-------+------------------+---------------------+----------------------- + 2 | 1 | 2 | 0 +(1 row) + +-- Cleanup +SELECT pg_stat_statements_reset() IS NOT NULL AS t; + t +--- + t +(1 row) + diff --git a/contrib/pg_stat_statements/expected/oldextversions.out b/contrib/pg_stat_statements/expected/oldextversions.out index 5a5404bbd57..ec317b0d6be 100644 --- a/contrib/pg_stat_statements/expected/oldextversions.out +++ b/contrib/pg_stat_statements/expected/oldextversions.out @@ -250,59 +250,61 @@ SELECT count(*) > 0 AS has_data FROM pg_stat_statements; t (1 row) --- New views for pg_stat_statements in 1.11 +-- New functions and views for pg_stat_statements in 1.11 AlTER EXTENSION pg_stat_statements UPDATE TO '1.11'; \d pg_stat_statements - View "public.pg_stat_statements" - Column | Type | Collation | Nullable | Default -------------------------+------------------+-----------+----------+--------- - userid | oid | | | - dbid | oid | | | - toplevel | boolean | | | - queryid | bigint | | | - query | text | | | - plans | bigint | | | - total_plan_time | double precision | | | - min_plan_time | double precision | | | - max_plan_time | double precision | | | - mean_plan_time | double precision | | | - stddev_plan_time | double precision | | | - calls | bigint | | | - total_exec_time | double precision | | | - min_exec_time | double precision | | | - max_exec_time | double precision | | | - mean_exec_time | double precision | | | - stddev_exec_time | double precision | | | - rows | bigint | | | - shared_blks_hit | bigint | | | - shared_blks_read | bigint | | | - shared_blks_dirtied | bigint | | | - shared_blks_written | bigint | | | - local_blks_hit | bigint | | | - local_blks_read | bigint | | | - local_blks_dirtied | bigint | | | - local_blks_written | bigint | | | - temp_blks_read | bigint | | | - temp_blks_written | bigint | | | - shared_blk_read_time | double precision | | | - shared_blk_write_time | double precision | | | - local_blk_read_time | double precision | | | - local_blk_write_time | double precision | | | - temp_blk_read_time | double precision | | | - temp_blk_write_time | double precision | | | - wal_records | bigint | | | - wal_fpi | bigint | | | - wal_bytes | numeric | | | - jit_functions | bigint | | | - jit_generation_time | double precision | | | - jit_inlining_count | bigint | | | - jit_inlining_time | double precision | | | - jit_optimization_count | bigint | | | - jit_optimization_time | double precision | | | - jit_emission_count | bigint | | | - jit_emission_time | double precision | | | - jit_deform_count | bigint | | | - jit_deform_time | double precision | | | + View "public.pg_stat_statements" + Column | Type | Collation | Nullable | Default +------------------------+--------------------------+-----------+----------+--------- + userid | oid | | | + dbid | oid | | | + toplevel | boolean | | | + queryid | bigint | | | + query | text | | | + plans | bigint | | | + total_plan_time | double precision | | | + min_plan_time | double precision | | | + max_plan_time | double precision | | | + mean_plan_time | double precision | | | + stddev_plan_time | double precision | | | + calls | bigint | | | + total_exec_time | double precision | | | + min_exec_time | double precision | | | + max_exec_time | double precision | | | + mean_exec_time | double precision | | | + stddev_exec_time | double precision | | | + rows | bigint | | | + shared_blks_hit | bigint | | | + shared_blks_read | bigint | | | + shared_blks_dirtied | bigint | | | + shared_blks_written | bigint | | | + local_blks_hit | bigint | | | + local_blks_read | bigint | | | + local_blks_dirtied | bigint | | | + local_blks_written | bigint | | | + temp_blks_read | bigint | | | + temp_blks_written | bigint | | | + shared_blk_read_time | double precision | | | + shared_blk_write_time | double precision | | | + local_blk_read_time | double precision | | | + local_blk_write_time | double precision | | | + temp_blk_read_time | double precision | | | + temp_blk_write_time | double precision | | | + wal_records | bigint | | | + wal_fpi | bigint | | | + wal_bytes | numeric | | | + jit_functions | bigint | | | + jit_generation_time | double precision | | | + jit_inlining_count | bigint | | | + jit_inlining_time | double precision | | | + jit_optimization_count | bigint | | | + jit_optimization_time | double precision | | | + jit_emission_count | bigint | | | + jit_emission_time | double precision | | | + jit_deform_count | bigint | | | + jit_deform_time | double precision | | | + stats_since | timestamp with time zone | | | + minmax_stats_since | timestamp with time zone | | | SELECT count(*) > 0 AS has_data FROM pg_stat_statements; has_data @@ -310,4 +312,16 @@ SELECT count(*) > 0 AS has_data FROM pg_stat_statements; t (1 row) +-- New parameter minmax_only of pg_stat_statements_reset function +SELECT pg_get_functiondef('pg_stat_statements_reset'::regproc); + pg_get_functiondef +------------------------------------------------------------------------------------------------------------------------------------------------------------------- + CREATE OR REPLACE FUNCTION public.pg_stat_statements_reset(userid oid DEFAULT 0, dbid oid DEFAULT 0, queryid bigint DEFAULT 0, minmax_only boolean DEFAULT false)+ + RETURNS timestamp with time zone + + LANGUAGE c + + PARALLEL SAFE STRICT + + AS '$libdir/pg_stat_statements', $function$pg_stat_statements_reset_1_11$function$ + + +(1 row) + DROP EXTENSION pg_stat_statements; diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build index 15b7c7f2b02..81fe1eb917d 100644 --- a/contrib/pg_stat_statements/meson.build +++ b/contrib/pg_stat_statements/meson.build @@ -49,6 +49,7 @@ tests += { 'planning', 'user_activity', 'wal', + 'entry_timestamp', 'cleanup', 'oldextversions', ], diff --git a/contrib/pg_stat_statements/pg_stat_statements--1.10--1.11.sql b/contrib/pg_stat_statements/pg_stat_statements--1.10--1.11.sql index 5fe211184bf..0bb2c397711 100644 --- a/contrib/pg_stat_statements/pg_stat_statements--1.10--1.11.sql +++ b/contrib/pg_stat_statements/pg_stat_statements--1.10--1.11.sql @@ -3,13 +3,10 @@ -- complain if script is sourced in psql, rather than via ALTER EXTENSION \echo Use "ALTER EXTENSION pg_stat_statements UPDATE TO '1.11'" 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 old versions */ DROP VIEW pg_stat_statements; DROP FUNCTION pg_stat_statements(boolean); +DROP FUNCTION pg_stat_statements_reset(Oid, Oid, bigint); /* Now redefine */ CREATE FUNCTION pg_stat_statements(IN showtext boolean, @@ -59,7 +56,9 @@ CREATE FUNCTION pg_stat_statements(IN showtext boolean, OUT jit_emission_count int8, OUT jit_emission_time float8, OUT jit_deform_count int8, - OUT jit_deform_time float8 + OUT jit_deform_time float8, + OUT stats_since timestamp with time zone, + OUT minmax_stats_since timestamp with time zone ) RETURNS SETOF record AS 'MODULE_PATHNAME', 'pg_stat_statements_1_11' @@ -69,3 +68,15 @@ CREATE VIEW pg_stat_statements AS SELECT * FROM pg_stat_statements(true); GRANT SELECT ON pg_stat_statements TO PUBLIC; + +CREATE FUNCTION pg_stat_statements_reset(IN userid Oid DEFAULT 0, + IN dbid Oid DEFAULT 0, + IN queryid bigint DEFAULT 0, + IN minmax_only boolean DEFAULT false +) +RETURNS timestamp with time zone +AS 'MODULE_PATHNAME', 'pg_stat_statements_reset_1_11' +LANGUAGE C STRICT PARALLEL SAFE; + +-- Don't want this to be available to non-superusers. +REVOKE ALL ON FUNCTION pg_stat_statements_reset(Oid, Oid, bigint, boolean) FROM PUBLIC; diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c index 6c63acf9898..16451763c5d 100644 --- a/contrib/pg_stat_statements/pg_stat_statements.c +++ b/contrib/pg_stat_statements/pg_stat_statements.c @@ -155,9 +155,9 @@ typedef struct Counters double total_time[PGSS_NUMKIND]; /* total planning/execution time, * in msec */ double min_time[PGSS_NUMKIND]; /* minimum planning/execution time in - * msec */ + * msec since min/max reset */ double max_time[PGSS_NUMKIND]; /* maximum planning/execution time in - * msec */ + * msec since min/max reset */ double mean_time[PGSS_NUMKIND]; /* mean planning/execution time in * msec */ double sum_var_time[PGSS_NUMKIND]; /* sum of variances in @@ -228,6 +228,8 @@ typedef struct pgssEntry Size query_offset; /* query text offset in external file */ int query_len; /* # of valid bytes in query string, or -1 */ int encoding; /* query text encoding */ + TimestampTz stats_since; /* timestamp of entry allocation */ + TimestampTz minmax_stats_since; /* timestamp of last min/max values reset */ slock_t mutex; /* protects the counters only */ } pgssEntry; @@ -308,6 +310,7 @@ static bool pgss_save = true; /* whether to save stats across shutdown */ PG_FUNCTION_INFO_V1(pg_stat_statements_reset); PG_FUNCTION_INFO_V1(pg_stat_statements_reset_1_7); +PG_FUNCTION_INFO_V1(pg_stat_statements_reset_1_11); PG_FUNCTION_INFO_V1(pg_stat_statements_1_2); PG_FUNCTION_INFO_V1(pg_stat_statements_1_3); PG_FUNCTION_INFO_V1(pg_stat_statements_1_8); @@ -359,7 +362,7 @@ static char *qtext_fetch(Size query_offset, int query_len, char *buffer, Size buffer_size); static bool need_gc_qtexts(void); static void gc_qtexts(void); -static void entry_reset(Oid userid, Oid dbid, uint64 queryid); +static TimestampTz entry_reset(Oid userid, Oid dbid, uint64 queryid, bool minmax_only); static char *generate_normalized_query(JumbleState *jstate, const char *query, int query_loc, int *query_len_p); static void fill_in_constant_lengths(JumbleState *jstate, const char *query, @@ -654,6 +657,8 @@ pgss_shmem_startup(void) /* copy in the actual stats */ entry->counters = temp.counters; + entry->stats_since = temp.stats_since; + entry->minmax_stats_since = temp.minmax_stats_since; } /* Read global statistics for pg_stat_statements */ @@ -1416,11 +1421,23 @@ pgss_store(const char *query, uint64 queryId, e->counters.sum_var_time[kind] += (total_time - old_mean) * (total_time - e->counters.mean_time[kind]); - /* calculate min and max time */ - if (e->counters.min_time[kind] > total_time) + /* + * Calculate min and max time. min = 0 and max = 0 + * means that the min/max statistics were reset + */ + if (e->counters.min_time[kind] == 0 + && e->counters.max_time[kind] == 0) + { e->counters.min_time[kind] = total_time; - if (e->counters.max_time[kind] < total_time) e->counters.max_time[kind] = total_time; + } + else + { + if (e->counters.min_time[kind] > total_time) + e->counters.min_time[kind] = total_time; + if (e->counters.max_time[kind] < total_time) + e->counters.max_time[kind] = total_time; + } } e->counters.rows += rows; e->counters.shared_blks_hit += bufusage->shared_blks_hit; @@ -1490,18 +1507,34 @@ pg_stat_statements_reset_1_7(PG_FUNCTION_ARGS) dbid = PG_GETARG_OID(1); queryid = (uint64) PG_GETARG_INT64(2); - entry_reset(userid, dbid, queryid); + entry_reset(userid, dbid, queryid, false); PG_RETURN_VOID(); } +Datum +pg_stat_statements_reset_1_11(PG_FUNCTION_ARGS) +{ + Oid userid; + Oid dbid; + uint64 queryid; + bool minmax_only; + + userid = PG_GETARG_OID(0); + dbid = PG_GETARG_OID(1); + queryid = (uint64) PG_GETARG_INT64(2); + minmax_only = PG_GETARG_BOOL(3); + + PG_RETURN_TIMESTAMPTZ(entry_reset(userid, dbid, queryid, minmax_only)); +} + /* * Reset statement statistics. */ Datum pg_stat_statements_reset(PG_FUNCTION_ARGS) { - entry_reset(0, 0, 0); + entry_reset(0, 0, 0, false); PG_RETURN_VOID(); } @@ -1514,8 +1547,8 @@ pg_stat_statements_reset(PG_FUNCTION_ARGS) #define PG_STAT_STATEMENTS_COLS_V1_8 32 #define PG_STAT_STATEMENTS_COLS_V1_9 33 #define PG_STAT_STATEMENTS_COLS_V1_10 43 -#define PG_STAT_STATEMENTS_COLS_V1_11 47 -#define PG_STAT_STATEMENTS_COLS 47 /* maximum of above */ +#define PG_STAT_STATEMENTS_COLS_V1_11 49 +#define PG_STAT_STATEMENTS_COLS 49 /* maximum of above */ /* * Retrieve statement statistics. @@ -1748,6 +1781,8 @@ pg_stat_statements_internal(FunctionCallInfo fcinfo, Counters tmp; double stddev; int64 queryid = entry->key.queryid; + TimestampTz stats_since; + TimestampTz minmax_stats_since; memset(values, 0, sizeof(values)); memset(nulls, 0, sizeof(nulls)); @@ -1816,6 +1851,8 @@ pg_stat_statements_internal(FunctionCallInfo fcinfo, SpinLockAcquire(&e->mutex); tmp = e->counters; + stats_since = e->stats_since; + minmax_stats_since = e->minmax_stats_since; SpinLockRelease(&e->mutex); } @@ -1912,6 +1949,8 @@ pg_stat_statements_internal(FunctionCallInfo fcinfo, { values[i++] = Int64GetDatumFast(tmp.jit_deform_count); values[i++] = Float8GetDatumFast(tmp.jit_deform_time); + values[i++] = TimestampTzGetDatum(stats_since); + values[i++] = TimestampTzGetDatum(minmax_stats_since); } Assert(i == (api_version == PGSS_V1_0 ? PG_STAT_STATEMENTS_COLS_V1_0 : @@ -2030,6 +2069,8 @@ entry_alloc(pgssHashKey *key, Size query_offset, int query_len, int encoding, entry->query_offset = query_offset; entry->query_len = query_len; entry->encoding = encoding; + entry->stats_since = GetCurrentTimestamp(); + entry->minmax_stats_since = entry->stats_since; } return entry; @@ -2593,11 +2634,30 @@ gc_fail: record_gc_qtexts(); } +#define SINGLE_ENTRY_RESET(e) \ +if (e) { \ + if (minmax_only) { \ + /* When requested reset only min/max statistics of an entry */ \ + for (int kind = 0; kind < PGSS_NUMKIND; kind++) \ + { \ + e->counters.max_time[kind] = 0; \ + e->counters.min_time[kind] = 0; \ + } \ + e->minmax_stats_since = stats_reset; \ + } \ + else \ + { \ + /* Remove the key otherwise */ \ + hash_search(pgss_hash, &e->key, HASH_REMOVE, NULL); \ + num_remove++; \ + } \ +} + /* - * Release entries corresponding to parameters passed. + * Reset entries corresponding to parameters passed. */ -static void -entry_reset(Oid userid, Oid dbid, uint64 queryid) +static TimestampTz +entry_reset(Oid userid, Oid dbid, uint64 queryid, bool minmax_only) { HASH_SEQ_STATUS hash_seq; pgssEntry *entry; @@ -2605,6 +2665,7 @@ entry_reset(Oid userid, Oid dbid, uint64 queryid) long num_entries; long num_remove = 0; pgssHashKey key; + TimestampTz stats_reset; if (!pgss || !pgss_hash) ereport(ERROR, @@ -2614,6 +2675,8 @@ entry_reset(Oid userid, Oid dbid, uint64 queryid) LWLockAcquire(pgss->lock, LW_EXCLUSIVE); num_entries = hash_get_num_entries(pgss_hash); + stats_reset = GetCurrentTimestamp(); + if (userid != 0 && dbid != 0 && queryid != UINT64CONST(0)) { /* If all the parameters are available, use the fast path. */ @@ -2623,22 +2686,22 @@ entry_reset(Oid userid, Oid dbid, uint64 queryid) key.queryid = queryid; /* - * Remove the key if it exists, starting with the non-top-level entry. + * Reset the entry if it exists, starting with the non-top-level entry. */ key.toplevel = false; - entry = (pgssEntry *) hash_search(pgss_hash, &key, HASH_REMOVE, NULL); - if (entry) /* found */ - num_remove++; + entry = (pgssEntry *) hash_search(pgss_hash, &key, HASH_FIND, NULL); - /* Also remove the top-level entry if it exists. */ + SINGLE_ENTRY_RESET(entry); + + /* Also reset the top-level entry if it exists. */ key.toplevel = true; - entry = (pgssEntry *) hash_search(pgss_hash, &key, HASH_REMOVE, NULL); - if (entry) /* found */ - num_remove++; + entry = (pgssEntry *) hash_search(pgss_hash, &key, HASH_FIND, NULL); + + SINGLE_ENTRY_RESET(entry); } else if (userid != 0 || dbid != 0 || queryid != UINT64CONST(0)) { - /* Remove entries corresponding to valid parameters. */ + /* Reset entries corresponding to valid parameters. */ hash_seq_init(&hash_seq, pgss_hash); while ((entry = hash_seq_search(&hash_seq)) != NULL) { @@ -2646,19 +2709,17 @@ entry_reset(Oid userid, Oid dbid, uint64 queryid) (!dbid || entry->key.dbid == dbid) && (!queryid || entry->key.queryid == queryid)) { - hash_search(pgss_hash, &entry->key, HASH_REMOVE, NULL); - num_remove++; + SINGLE_ENTRY_RESET(entry); } } } else { - /* Remove all entries. */ + /* Reset all entries. */ hash_seq_init(&hash_seq, pgss_hash); while ((entry = hash_seq_search(&hash_seq)) != NULL) { - hash_search(pgss_hash, &entry->key, HASH_REMOVE, NULL); - num_remove++; + SINGLE_ENTRY_RESET(entry); } } @@ -2672,7 +2733,6 @@ entry_reset(Oid userid, Oid dbid, uint64 queryid) */ { volatile pgssSharedState *s = (volatile pgssSharedState *) pgss; - TimestampTz stats_reset = GetCurrentTimestamp(); SpinLockAcquire(&s->mutex); s->stats.dealloc = 0; @@ -2710,6 +2770,8 @@ done: release_lock: LWLockRelease(pgss->lock); + + return stats_reset; } /* diff --git a/contrib/pg_stat_statements/sql/entry_timestamp.sql b/contrib/pg_stat_statements/sql/entry_timestamp.sql new file mode 100644 index 00000000000..d6d3027ab4f --- /dev/null +++ b/contrib/pg_stat_statements/sql/entry_timestamp.sql @@ -0,0 +1,114 @@ +-- +-- statement timestamps +-- + +-- planning time is needed during tests +SET pg_stat_statements.track_planning = TRUE; + +SELECT 1 AS "STMTTS1"; +SELECT now() AS ref_ts \gset +SELECT 1,2 AS "STMTTS2"; +SELECT stats_since >= :'ref_ts', count(*) FROM pg_stat_statements +WHERE query LIKE '%STMTTS%' +GROUP BY stats_since >= :'ref_ts' +ORDER BY stats_since >= :'ref_ts'; + +SELECT now() AS ref_ts \gset +SELECT + count(*) as total, + count(*) FILTER ( + WHERE min_plan_time + max_plan_time = 0 + ) as minmax_plan_zero, + count(*) FILTER ( + WHERE min_exec_time + max_exec_time = 0 + ) as minmax_exec_zero, + count(*) FILTER ( + WHERE minmax_stats_since >= :'ref_ts' + ) as minmax_stats_since_after_ref, + count(*) FILTER ( + WHERE stats_since >= :'ref_ts' + ) as stats_since_after_ref +FROM pg_stat_statements +WHERE query LIKE '%STMTTS%'; + +-- Perform single min/max reset +SELECT pg_stat_statements_reset(0, 0, queryid, true) AS minmax_reset_ts +FROM pg_stat_statements +WHERE query LIKE '%STMTTS1%' \gset + +-- check +SELECT + count(*) as total, + count(*) FILTER ( + WHERE min_plan_time + max_plan_time = 0 + ) as minmax_plan_zero, + count(*) FILTER ( + WHERE min_exec_time + max_exec_time = 0 + ) as minmax_exec_zero, + count(*) FILTER ( + WHERE minmax_stats_since >= :'ref_ts' + ) as minmax_stats_since_after_ref, + count(*) FILTER ( + WHERE stats_since >= :'ref_ts' + ) as stats_since_after_ref +FROM pg_stat_statements +WHERE query LIKE '%STMTTS%'; + +-- check minmax reset timestamps +SELECT +query, minmax_stats_since = :'minmax_reset_ts' AS reset_ts_match +FROM pg_stat_statements +WHERE query LIKE '%STMTTS%' +ORDER BY query COLLATE "C"; + +-- check that minmax reset does not set stats_reset +SELECT +stats_reset = :'minmax_reset_ts' AS stats_reset_ts_match +FROM pg_stat_statements_info; + +-- Perform common min/max reset +SELECT pg_stat_statements_reset(0, 0, 0, true) AS minmax_reset_ts \gset + +-- check again +SELECT + count(*) as total, + count(*) FILTER ( + WHERE min_plan_time + max_plan_time = 0 + ) as minmax_plan_zero, + count(*) FILTER ( + WHERE min_exec_time + max_exec_time = 0 + ) as minmax_exec_zero, + count(*) FILTER ( + WHERE minmax_stats_since >= :'ref_ts' + ) as minmax_ts_after_ref, + count(*) FILTER ( + WHERE minmax_stats_since = :'minmax_reset_ts' + ) as minmax_ts_match, + count(*) FILTER ( + WHERE stats_since >= :'ref_ts' + ) as stats_since_after_ref +FROM pg_stat_statements +WHERE query LIKE '%STMTTS%'; + +-- Execute first query once more to check stats update +SELECT 1 AS "STMTTS1"; + +-- check +-- we don't check planing times here to be independent of +-- plan caching approach +SELECT + count(*) as total, + count(*) FILTER ( + WHERE min_exec_time + max_exec_time = 0 + ) as minmax_exec_zero, + count(*) FILTER ( + WHERE minmax_stats_since >= :'ref_ts' + ) as minmax_ts_after_ref, + count(*) FILTER ( + WHERE stats_since >= :'ref_ts' + ) as stats_since_after_ref +FROM pg_stat_statements +WHERE query LIKE '%STMTTS%'; + +-- Cleanup +SELECT pg_stat_statements_reset() IS NOT NULL AS t; diff --git a/contrib/pg_stat_statements/sql/oldextversions.sql b/contrib/pg_stat_statements/sql/oldextversions.sql index 2435c0c576e..ec06caa5ddc 100644 --- a/contrib/pg_stat_statements/sql/oldextversions.sql +++ b/contrib/pg_stat_statements/sql/oldextversions.sql @@ -48,9 +48,11 @@ AlTER EXTENSION pg_stat_statements UPDATE TO '1.10'; \d pg_stat_statements SELECT count(*) > 0 AS has_data FROM pg_stat_statements; --- New views for pg_stat_statements in 1.11 +-- New functions and views for pg_stat_statements in 1.11 AlTER EXTENSION pg_stat_statements UPDATE TO '1.11'; \d pg_stat_statements SELECT count(*) > 0 AS has_data FROM pg_stat_statements; +-- New parameter minmax_only of pg_stat_statements_reset function +SELECT pg_get_functiondef('pg_stat_statements_reset'::regproc); DROP EXTENSION pg_stat_statements; diff --git a/doc/src/sgml/pgstatstatements.sgml b/doc/src/sgml/pgstatstatements.sgml index b66dc7fa30a..acfacf828ce 100644 --- a/doc/src/sgml/pgstatstatements.sgml +++ b/doc/src/sgml/pgstatstatements.sgml @@ -140,9 +140,12 @@ min_plan_time double precision - Minimum time spent planning the statement, in milliseconds - (if pg_stat_statements.track_planning is enabled, - otherwise zero) + Minimum time spent planning the statement, in milliseconds. + This field will be zero if pg_stat_statements.track_planning + is disabled, or if the counter has been reset using the + pg_stat_statements_reset function with the + minmax_only parameter set to true + and never been planned since. @@ -151,9 +154,12 @@ max_plan_time double precision - Maximum time spent planning the statement, in milliseconds - (if pg_stat_statements.track_planning is enabled, - otherwise zero) + Maximum time spent planning the statement, in milliseconds. + This field will be zero if pg_stat_statements.track_planning + is disabled, or if the counter has been reset using the + pg_stat_statements_reset function with the + minmax_only parameter set to true + and never been planned since. @@ -203,7 +209,11 @@ min_exec_time double precision - Minimum time spent executing the statement, in milliseconds + Minimum time spent executing the statement, in milliseconds, + this field will be zero until this statement + is executed first time after reset performed by the + pg_stat_statements_reset function with the + minmax_only parameter set to true @@ -212,7 +222,11 @@ max_exec_time double precision - Maximum time spent executing the statement, in milliseconds + Maximum time spent executing the statement, in milliseconds, + this field will be zero until this statement + is executed first time after reset performed by the + pg_stat_statements_reset function with the + minmax_only parameter set to true @@ -512,6 +526,28 @@ functions, in milliseconds + + + + stats_since timestamp with time zone + + + Time at which statistics gathering started for this statement + + + + + + minmax_stats_since timestamp with time zone + + + Time at which min/max statistics gathering started for this + statement (fields min_plan_time, + max_plan_time, + min_exec_time and + max_exec_time) + + @@ -713,7 +749,8 @@ - pg_stat_statements_reset(userid Oid, dbid Oid, queryid bigint) returns void + pg_stat_statements_reset(userid Oid, dbid Oid, queryid + bigint, minmax_only boolean) returns timestamp with time zone pg_stat_statements_reset @@ -732,6 +769,20 @@ If all statistics in the pg_stat_statements view are discarded, it will also reset the statistics in the pg_stat_statements_info view. + When minmax_only is true only the + values of minimun and maximum planning and execution time will be reset (i.e. + min_plan_time, max_plan_time, + min_exec_time and max_exec_time + fields). The default value for minmax_only parameter is + false. Time of last min/max reset performed is shown in + minmax_stats_since field of the + pg_stat_statements view. + This function returns the time of a reset. This time is saved to + stats_reset field of + pg_stat_statements_info view or to + minmax_stats_since field of the + pg_stat_statements view if the corresponding reset was + actually performed. By default, this function can only be executed by superusers. Access may be granted to others using GRANT. -- 2.39.3 (Apple Git-145)