diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/backend/utils/activity/pgstat.c | 233 | ||||
-rw-r--r-- | src/backend/utils/activity/pgstat_shmem.c | 31 | ||||
-rw-r--r-- | src/backend/utils/adt/pgstatfuncs.c | 2 | ||||
-rw-r--r-- | src/include/pgstat.h | 36 | ||||
-rw-r--r-- | src/include/utils/pgstat_internal.h | 22 |
5 files changed, 291 insertions, 33 deletions
diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c index 2e13670fc1f..b2ca3f39b7a 100644 --- a/src/backend/utils/activity/pgstat.c +++ b/src/backend/utils/activity/pgstat.c @@ -49,8 +49,16 @@ * pgStatPending list. Pending statistics updates are flushed out by * pgstat_report_stat(). * + * It is possible for external modules to define custom statistics kinds, + * that can use the same properties as any built-in stats kinds. Each custom + * stats kind needs to assign a unique ID to ensure that it does not overlap + * with other extensions. In order to reserve a unique stats kind ID, refer + * to https://wiki.postgresql.org/wiki/CustomCumulativeStats. + * * The behavior of different kinds of statistics is determined by the kind's - * entry in pgstat_kind_infos, see PgStat_KindInfo for details. + * entry in pgstat_kind_builtin_infos for all the built-in statistics kinds + * defined, and pgstat_kind_custom_infos for custom kinds registered at + * startup by pgstat_register_kind(). See PgStat_KindInfo for details. * * The consistency of read accesses to statistics can be configured using the * stats_fetch_consistency GUC (see config.sgml and monitoring.sgml for the @@ -175,6 +183,8 @@ typedef struct PgStat_SnapshotEntry static void pgstat_write_statsfile(XLogRecPtr redo); static void pgstat_read_statsfile(XLogRecPtr redo); +static void pgstat_init_snapshot_fixed(void); + static void pgstat_reset_after_failure(void); static bool pgstat_flush_pending_entries(bool nowait); @@ -252,7 +262,7 @@ static bool pgstat_is_shutdown = false; /* - * The different kinds of statistics. + * The different kinds of built-in statistics. * * If reasonably possible, handling specific to one kind of stats should go * through this abstraction, rather than making more of pgstat.c aware. @@ -264,7 +274,7 @@ static bool pgstat_is_shutdown = false; * seem to be a great way of doing that, given the split across multiple * files. */ -static const PgStat_KindInfo pgstat_kind_infos[PGSTAT_NUM_KINDS] = { +static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE] = { /* stats kinds for variable-numbered objects */ @@ -437,6 +447,15 @@ static const PgStat_KindInfo pgstat_kind_infos[PGSTAT_NUM_KINDS] = { }, }; +/* + * Information about custom statistics kinds. + * + * These are saved in a different array than the built-in kinds to save + * in clarity with the initializations. + * + * Indexed by PGSTAT_KIND_CUSTOM_MIN, of size PGSTAT_KIND_CUSTOM_SIZE. + */ +static const PgStat_KindInfo **pgstat_kind_custom_infos = NULL; /* ------------------------------------------------------------ * Functions managing the state of the stats system for all backends. @@ -587,6 +606,8 @@ pgstat_initialize(void) pgstat_init_wal(); + pgstat_init_snapshot_fixed(); + /* Set up a process-exit hook to clean up */ before_shmem_exit(pgstat_shutdown_hook, 0); @@ -830,6 +851,8 @@ pgstat_clear_snapshot(void) memset(&pgStatLocal.snapshot.fixed_valid, 0, sizeof(pgStatLocal.snapshot.fixed_valid)); + memset(&pgStatLocal.snapshot.custom_valid, 0, + sizeof(pgStatLocal.snapshot.custom_valid)); pgStatLocal.snapshot.stats = NULL; pgStatLocal.snapshot.mode = PGSTAT_FETCH_CONSISTENCY_NONE; @@ -993,7 +1016,29 @@ pgstat_snapshot_fixed(PgStat_Kind kind) else pgstat_build_snapshot_fixed(kind); - Assert(pgStatLocal.snapshot.fixed_valid[kind]); + if (pgstat_is_kind_builtin(kind)) + Assert(pgStatLocal.snapshot.fixed_valid[kind]); + else if (pgstat_is_kind_custom(kind)) + Assert(pgStatLocal.snapshot.custom_valid[kind - PGSTAT_KIND_CUSTOM_MIN]); +} + +static void +pgstat_init_snapshot_fixed(void) +{ + /* + * Initialize fixed-numbered statistics data in snapshots, only for custom + * stats kinds. + */ + for (PgStat_Kind kind = PGSTAT_KIND_CUSTOM_MIN; kind <= PGSTAT_KIND_CUSTOM_MAX; kind++) + { + const PgStat_KindInfo *kind_info = pgstat_get_kind_info(kind); + + if (!kind_info || !kind_info->fixed_amount) + continue; + + pgStatLocal.snapshot.custom_data[kind - PGSTAT_KIND_CUSTOM_MIN] = + MemoryContextAlloc(TopMemoryContext, kind_info->shared_data_len); + } } static void @@ -1089,10 +1134,12 @@ pgstat_build_snapshot(void) /* * Build snapshot of all fixed-numbered stats. */ - for (PgStat_Kind kind = PGSTAT_KIND_FIRST_VALID; kind <= PGSTAT_KIND_LAST; kind++) + for (PgStat_Kind kind = PGSTAT_KIND_MIN; kind <= PGSTAT_KIND_MAX; kind++) { const PgStat_KindInfo *kind_info = pgstat_get_kind_info(kind); + if (!kind_info) + continue; if (!kind_info->fixed_amount) { Assert(kind_info->snapshot_cb == NULL); @@ -1109,6 +1156,20 @@ static void pgstat_build_snapshot_fixed(PgStat_Kind kind) { const PgStat_KindInfo *kind_info = pgstat_get_kind_info(kind); + int idx; + bool *valid; + + /* Position in fixed_valid or custom_valid */ + if (pgstat_is_kind_builtin(kind)) + { + idx = kind; + valid = pgStatLocal.snapshot.fixed_valid; + } + else + { + idx = kind - PGSTAT_KIND_CUSTOM_MIN; + valid = pgStatLocal.snapshot.custom_valid; + } Assert(kind_info->fixed_amount); Assert(kind_info->snapshot_cb != NULL); @@ -1116,21 +1177,21 @@ pgstat_build_snapshot_fixed(PgStat_Kind kind) if (pgstat_fetch_consistency == PGSTAT_FETCH_CONSISTENCY_NONE) { /* rebuild every time */ - pgStatLocal.snapshot.fixed_valid[kind] = false; + valid[idx] = false; } - else if (pgStatLocal.snapshot.fixed_valid[kind]) + else if (valid[idx]) { /* in snapshot mode we shouldn't get called again */ Assert(pgstat_fetch_consistency == PGSTAT_FETCH_CONSISTENCY_CACHE); return; } - Assert(!pgStatLocal.snapshot.fixed_valid[kind]); + Assert(!valid[idx]); kind_info->snapshot_cb(); - Assert(!pgStatLocal.snapshot.fixed_valid[kind]); - pgStatLocal.snapshot.fixed_valid[kind] = true; + Assert(!valid[idx]); + valid[idx] = true; } @@ -1286,30 +1347,131 @@ pgstat_flush_pending_entries(bool nowait) PgStat_Kind pgstat_get_kind_from_str(char *kind_str) { - for (PgStat_Kind kind = PGSTAT_KIND_FIRST_VALID; kind <= PGSTAT_KIND_LAST; kind++) + for (PgStat_Kind kind = PGSTAT_KIND_BUILTIN_MIN; kind <= PGSTAT_KIND_BUILTIN_MAX; kind++) { - if (pg_strcasecmp(kind_str, pgstat_kind_infos[kind].name) == 0) + if (pg_strcasecmp(kind_str, pgstat_kind_builtin_infos[kind].name) == 0) return kind; } + /* Check the custom set of cumulative stats */ + if (pgstat_kind_custom_infos) + { + for (PgStat_Kind kind = PGSTAT_KIND_CUSTOM_MIN; kind <= PGSTAT_KIND_CUSTOM_MAX; kind++) + { + uint32 idx = kind - PGSTAT_KIND_CUSTOM_MIN; + + if (pgstat_kind_custom_infos[idx] && + pg_strcasecmp(kind_str, pgstat_kind_custom_infos[idx]->name) == 0) + return kind; + } + } + ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("invalid statistics kind: \"%s\"", kind_str))); - return PGSTAT_KIND_DATABASE; /* avoid compiler warnings */ + return PGSTAT_KIND_INVALID; /* avoid compiler warnings */ } static inline bool pgstat_is_kind_valid(PgStat_Kind kind) { - return kind >= PGSTAT_KIND_FIRST_VALID && kind <= PGSTAT_KIND_LAST; + return pgstat_is_kind_builtin(kind) || pgstat_is_kind_custom(kind); } const PgStat_KindInfo * pgstat_get_kind_info(PgStat_Kind kind) { - Assert(pgstat_is_kind_valid(kind)); + if (pgstat_is_kind_builtin(kind)) + return &pgstat_kind_builtin_infos[kind]; + + if (pgstat_is_kind_custom(kind)) + { + uint32 idx = kind - PGSTAT_KIND_CUSTOM_MIN; - return &pgstat_kind_infos[kind]; + if (pgstat_kind_custom_infos == NULL || + pgstat_kind_custom_infos[idx] == NULL) + return NULL; + return pgstat_kind_custom_infos[idx]; + } + + return NULL; +} + +/* + * Register a new stats kind. + * + * PgStat_Kinds must be globally unique across all extensions. Refer + * to https://wiki.postgresql.org/wiki/CustomCumulativeStats to reserve a + * unique ID for your extension, to avoid conflicts with other extension + * developers. During development, use PGSTAT_KIND_EXPERIMENTAL to avoid + * needlessly reserving a new ID. + */ +void +pgstat_register_kind(PgStat_Kind kind, const PgStat_KindInfo *kind_info) +{ + uint32 idx = kind - PGSTAT_KIND_CUSTOM_MIN; + + if (kind_info->name == NULL || strlen(kind_info->name) == 0) + ereport(ERROR, + (errmsg("custom cumulative statistics name is invalid"), + errhint("Provide a non-empty name for the custom cumulative statistics."))); + + if (!pgstat_is_kind_custom(kind)) + ereport(ERROR, (errmsg("custom cumulative statistics ID %u is out of range", kind), + errhint("Provide a custom cumulative statistics ID between %u and %u.", + PGSTAT_KIND_CUSTOM_MIN, PGSTAT_KIND_CUSTOM_MAX))); + + if (!process_shared_preload_libraries_in_progress) + ereport(ERROR, + (errmsg("failed to register custom cumulative statistics \"%s\" with ID %u", kind_info->name, kind), + errdetail("Custom cumulative statistics must be registered while initializing modules in \"shared_preload_libraries\"."))); + + /* + * Check some data for fixed-numbered stats. + */ + if (kind_info->fixed_amount) + { + if (kind_info->shared_size == 0) + ereport(ERROR, + (errmsg("custom cumulative statistics property is invalid"), + errhint("Custom cumulative statistics require a shared memory size for fixed-numbered objects."))); + } + + /* + * If pgstat_kind_custom_infos is not available yet, allocate it. + */ + if (pgstat_kind_custom_infos == NULL) + { + pgstat_kind_custom_infos = (const PgStat_KindInfo **) + MemoryContextAllocZero(TopMemoryContext, + sizeof(PgStat_KindInfo *) * PGSTAT_KIND_CUSTOM_SIZE); + } + + if (pgstat_kind_custom_infos[idx] != NULL && + pgstat_kind_custom_infos[idx]->name != NULL) + ereport(ERROR, + (errmsg("failed to register custom cumulative statistics \"%s\" with ID %u", kind_info->name, kind), + errdetail("Custom cumulative statistics \"%s\" already registered with the same ID.", + pgstat_kind_custom_infos[idx]->name))); + + /* check for existing custom stats with the same name */ + for (PgStat_Kind existing_kind = PGSTAT_KIND_CUSTOM_MIN; existing_kind <= PGSTAT_KIND_CUSTOM_MAX; existing_kind++) + { + uint32 existing_idx = existing_kind - PGSTAT_KIND_CUSTOM_MIN; + + if (pgstat_kind_custom_infos[existing_idx] == NULL) + continue; + if (!pg_strcasecmp(pgstat_kind_custom_infos[existing_idx]->name, kind_info->name)) + ereport(ERROR, + (errmsg("failed to register custom cumulative statistics \"%s\" with ID %u", kind_info->name, kind), + errdetail("Existing cumulative statistics with ID %u has the same name.", existing_kind))); + } + + /* Register it */ + pgstat_kind_custom_infos[idx] = kind_info; + ereport(LOG, + (errmsg("registered custom cumulative statistics \"%s\" with ID %u", + kind_info->name, kind))); } /* @@ -1393,18 +1555,22 @@ pgstat_write_statsfile(XLogRecPtr redo) write_chunk_s(fpout, &redo); /* Write various stats structs for fixed number of objects */ - for (PgStat_Kind kind = PGSTAT_KIND_FIRST_VALID; kind <= PGSTAT_KIND_LAST; kind++) + for (PgStat_Kind kind = PGSTAT_KIND_MIN; kind <= PGSTAT_KIND_MAX; kind++) { char *ptr; const PgStat_KindInfo *info = pgstat_get_kind_info(kind); - if (!info->fixed_amount) + if (!info || !info->fixed_amount) continue; - Assert(info->snapshot_ctl_off != 0); + if (pgstat_is_kind_builtin(kind)) + Assert(info->snapshot_ctl_off != 0); pgstat_build_snapshot_fixed(kind); - ptr = ((char *) &pgStatLocal.snapshot) + info->snapshot_ctl_off; + if (pgstat_is_kind_builtin(kind)) + ptr = ((char *) &pgStatLocal.snapshot) + info->snapshot_ctl_off; + else + ptr = pgStatLocal.snapshot.custom_data[kind - PGSTAT_KIND_CUSTOM_MIN]; fputc(PGSTAT_FILE_ENTRY_FIXED, fpout); write_chunk_s(fpout, &kind); @@ -1427,6 +1593,17 @@ pgstat_write_statsfile(XLogRecPtr redo) if (ps->dropped) continue; + /* + * This discards data related to custom stats kinds that are unknown + * to this process. + */ + if (!pgstat_is_kind_valid(ps->key.kind)) + { + elog(WARNING, "found unknown stats entry %u/%u/%u", + ps->key.kind, ps->key.dboid, ps->key.objoid); + continue; + } + shstats = (PgStatShared_Common *) dsa_get_address(pgStatLocal.dsa, ps->body); kind_info = pgstat_get_kind_info(ps->key.kind); @@ -1613,8 +1790,16 @@ pgstat_read_statsfile(XLogRecPtr redo) } /* Load back stats into shared memory */ - ptr = ((char *) shmem) + info->shared_ctl_off + - info->shared_data_off; + if (pgstat_is_kind_builtin(kind)) + ptr = ((char *) shmem) + info->shared_ctl_off + + info->shared_data_off; + else + { + int idx = kind - PGSTAT_KIND_CUSTOM_MIN; + + ptr = ((char *) shmem->custom_data[idx]) + + info->shared_data_off; + } if (!read_chunk(fpin, ptr, info->shared_data_len)) { @@ -1777,11 +1962,11 @@ pgstat_reset_after_failure(void) TimestampTz ts = GetCurrentTimestamp(); /* reset fixed-numbered stats */ - for (PgStat_Kind kind = PGSTAT_KIND_FIRST_VALID; kind <= PGSTAT_KIND_LAST; kind++) + for (PgStat_Kind kind = PGSTAT_KIND_MIN; kind <= PGSTAT_KIND_MAX; kind++) { const PgStat_KindInfo *kind_info = pgstat_get_kind_info(kind); - if (!kind_info->fixed_amount) + if (!kind_info || !kind_info->fixed_amount) continue; kind_info->reset_all_cb(ts); diff --git a/src/backend/utils/activity/pgstat_shmem.c b/src/backend/utils/activity/pgstat_shmem.c index 2d5f7d46de7..fd09b9d988b 100644 --- a/src/backend/utils/activity/pgstat_shmem.c +++ b/src/backend/utils/activity/pgstat_shmem.c @@ -131,6 +131,21 @@ StatsShmemSize(void) sz = MAXALIGN(sizeof(PgStat_ShmemControl)); sz = add_size(sz, pgstat_dsa_init_size()); + /* Add shared memory for all the custom fixed-numbered statistics */ + for (PgStat_Kind kind = PGSTAT_KIND_CUSTOM_MIN; kind <= PGSTAT_KIND_CUSTOM_MAX; kind++) + { + const PgStat_KindInfo *kind_info = pgstat_get_kind_info(kind); + + if (!kind_info) + continue; + if (!kind_info->fixed_amount) + continue; + + Assert(kind_info->shared_size != 0); + + sz += MAXALIGN(kind_info->shared_size); + } + return sz; } @@ -197,15 +212,25 @@ StatsShmemInit(void) pg_atomic_init_u64(&ctl->gc_request_count, 1); /* initialize fixed-numbered stats */ - for (PgStat_Kind kind = PGSTAT_KIND_FIRST_VALID; kind <= PGSTAT_KIND_LAST; kind++) + for (PgStat_Kind kind = PGSTAT_KIND_MIN; kind <= PGSTAT_KIND_MAX; kind++) { const PgStat_KindInfo *kind_info = pgstat_get_kind_info(kind); char *ptr; - if (!kind_info->fixed_amount) + if (!kind_info || !kind_info->fixed_amount) continue; - ptr = ((char *) ctl) + kind_info->shared_ctl_off; + if (pgstat_is_kind_builtin(kind)) + ptr = ((char *) ctl) + kind_info->shared_ctl_off; + else + { + int idx = kind - PGSTAT_KIND_CUSTOM_MIN; + + Assert(kind_info->shared_size != 0); + ctl->custom_data[idx] = ShmemAlloc(kind_info->shared_size); + ptr = ctl->custom_data[idx]; + } + kind_info->init_shmem_cb(ptr); } } diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c index 3876339ee1b..32211371237 100644 --- a/src/backend/utils/adt/pgstatfuncs.c +++ b/src/backend/utils/adt/pgstatfuncs.c @@ -1696,7 +1696,7 @@ pg_stat_reset(PG_FUNCTION_ARGS) * Reset some shared cluster-wide counters * * When adding a new reset target, ideally the name should match that in - * pgstat_kind_infos, if relevant. + * pgstat_kind_builtin_infos, if relevant. */ Datum pg_stat_reset_shared(PG_FUNCTION_ARGS) diff --git a/src/include/pgstat.h b/src/include/pgstat.h index f84e9fdeca5..f63159c55ca 100644 --- a/src/include/pgstat.h +++ b/src/include/pgstat.h @@ -35,6 +35,10 @@ /* The types of statistics entries */ #define PgStat_Kind uint32 +/* Range of IDs allowed, for built-in and custom kinds */ +#define PGSTAT_KIND_MIN 1 /* Minimum ID allowed */ +#define PGSTAT_KIND_MAX 256 /* Maximum ID allowed */ + /* use 0 for INVALID, to catch zero-initialized data */ #define PGSTAT_KIND_INVALID 0 @@ -53,9 +57,35 @@ #define PGSTAT_KIND_SLRU 10 #define PGSTAT_KIND_WAL 11 -#define PGSTAT_KIND_FIRST_VALID PGSTAT_KIND_DATABASE -#define PGSTAT_KIND_LAST PGSTAT_KIND_WAL -#define PGSTAT_NUM_KINDS (PGSTAT_KIND_LAST + 1) +#define PGSTAT_KIND_BUILTIN_MIN PGSTAT_KIND_DATABASE +#define PGSTAT_KIND_BUILTIN_MAX PGSTAT_KIND_WAL +#define PGSTAT_KIND_BUILTIN_SIZE (PGSTAT_KIND_BUILTIN_MAX + 1) + +/* Custom stats kinds */ + +/* Range of IDs allowed for custom stats kinds */ +#define PGSTAT_KIND_CUSTOM_MIN 128 +#define PGSTAT_KIND_CUSTOM_MAX PGSTAT_KIND_MAX +#define PGSTAT_KIND_CUSTOM_SIZE (PGSTAT_KIND_CUSTOM_MAX - PGSTAT_KIND_CUSTOM_MIN + 1) + +/* + * PgStat_Kind to use for extensions that require an ID, but are still in + * development and have not reserved their own unique kind ID yet. See: + * https://wiki.postgresql.org/wiki/CustomCumulativeStats + */ +#define PGSTAT_KIND_EXPERIMENTAL 128 + +static inline bool +pgstat_is_kind_builtin(PgStat_Kind kind) +{ + return kind >= PGSTAT_KIND_BUILTIN_MIN && kind <= PGSTAT_KIND_BUILTIN_MAX; +} + +static inline bool +pgstat_is_kind_custom(PgStat_Kind kind) +{ + return kind >= PGSTAT_KIND_CUSTOM_MIN && kind <= PGSTAT_KIND_CUSTOM_MAX; +} /* Values for track_functions GUC variable --- order is significant! */ typedef enum TrackFunctionsLevel diff --git a/src/include/utils/pgstat_internal.h b/src/include/utils/pgstat_internal.h index 778f625ca1d..26b4b784060 100644 --- a/src/include/utils/pgstat_internal.h +++ b/src/include/utils/pgstat_internal.h @@ -195,7 +195,8 @@ typedef struct PgStat_KindInfo /* * The size of an entry in the shared stats hash table (pointed to by - * PgStatShared_HashEntry->body). + * PgStatShared_HashEntry->body). For fixed-numbered statistics, this is + * the size of an entry in PgStat_ShmemControl->custom_data. */ uint32 shared_size; @@ -446,6 +447,13 @@ typedef struct PgStat_ShmemControl PgStatShared_IO io; PgStatShared_SLRU slru; PgStatShared_Wal wal; + + /* + * Custom stats data with fixed-numbered objects, indexed by (PgStat_Kind + * - PGSTAT_KIND_CUSTOM_MIN). + */ + void *custom_data[PGSTAT_KIND_CUSTOM_SIZE]; + } PgStat_ShmemControl; @@ -459,7 +467,7 @@ typedef struct PgStat_Snapshot /* time at which snapshot was taken */ TimestampTz snapshot_timestamp; - bool fixed_valid[PGSTAT_NUM_KINDS]; + bool fixed_valid[PGSTAT_KIND_BUILTIN_SIZE]; PgStat_ArchiverStats archiver; @@ -473,6 +481,14 @@ typedef struct PgStat_Snapshot PgStat_WalStats wal; + /* + * Data in snapshot for custom fixed-numbered statistics, indexed by + * (PgStat_Kind - PGSTAT_KIND_CUSTOM_MIN). Each entry is allocated in + * TopMemoryContext, for a size of PgStat_KindInfo->shared_data_len. + */ + bool custom_valid[PGSTAT_KIND_CUSTOM_SIZE]; + void *custom_data[PGSTAT_KIND_CUSTOM_SIZE]; + /* to free snapshot in bulk */ MemoryContext context; struct pgstat_snapshot_hash *stats; @@ -516,6 +532,8 @@ static inline void *pgstat_get_entry_data(PgStat_Kind kind, PgStatShared_Common */ extern const PgStat_KindInfo *pgstat_get_kind_info(PgStat_Kind kind); +extern void pgstat_register_kind(PgStat_Kind kind, + const PgStat_KindInfo *kind_info); #ifdef USE_ASSERT_CHECKING extern void pgstat_assert_is_up(void); |