diff options
Diffstat (limited to 'src/backend/utils/activity/pgstat_function.c')
| -rw-r--r-- | src/backend/utils/activity/pgstat_function.c | 167 |
1 files changed, 82 insertions, 85 deletions
diff --git a/src/backend/utils/activity/pgstat_function.c b/src/backend/utils/activity/pgstat_function.c index ad9879afb2a..427d8c47fc6 100644 --- a/src/backend/utils/activity/pgstat_function.c +++ b/src/backend/utils/activity/pgstat_function.c @@ -17,8 +17,10 @@ #include "postgres.h" +#include "fmgr.h" +#include "utils/inval.h" #include "utils/pgstat_internal.h" -#include "utils/timestamp.h" +#include "utils/syscache.h" /* ---------- @@ -29,18 +31,6 @@ int pgstat_track_functions = TRACK_FUNC_OFF; /* - * Indicates if backend has some function stats that it hasn't yet - * sent to the collector. - */ -bool have_function_stats = false; - -/* - * Backends store per-function info that's waiting to be sent to the collector - * in this hash table (indexed by function OID). - */ -static HTAB *pgStatFunctions = NULL; - -/* * Total time charged to functions so far in the current backend. * We use this to help separate "self" and "other" time charges. * (We assume this initializes to zero.) @@ -61,6 +51,10 @@ pgstat_create_function(Oid proid) /* * Ensure that stats are dropped if transaction commits. + * + * NB: This is only reliable because pgstat_init_function_usage() does some + * extra work. If other places start emitting function stats they likely need + * similar logic. */ void pgstat_drop_function(Oid proid) @@ -78,8 +72,9 @@ void pgstat_init_function_usage(FunctionCallInfo fcinfo, PgStat_FunctionCallUsage *fcu) { - PgStat_BackendFunctionEntry *htabent; - bool found; + PgStat_EntryRef *entry_ref; + PgStat_BackendFunctionEntry *pending; + bool created_entry; if (pgstat_track_functions <= fcinfo->flinfo->fn_stats) { @@ -88,29 +83,48 @@ pgstat_init_function_usage(FunctionCallInfo fcinfo, return; } - if (!pgStatFunctions) + entry_ref = pgstat_prep_pending_entry(PGSTAT_KIND_FUNCTION, + MyDatabaseId, + fcinfo->flinfo->fn_oid, + &created_entry); + + /* + * If no shared entry already exists, check if the function has been + * deleted concurrently. This can go unnoticed until here because + * executing a statement that just calls a function, does not trigger + * cache invalidation processing. The reason we care about this case is + * that otherwise we could create a new stats entry for an already dropped + * function (for relations etc this is not possible because emitting stats + * requires a lock for the relation to already have been acquired). + * + * It's somewhat ugly to have a behavioral difference based on + * track_functions being enabled/disabled. But it seems acceptable, given + * that there's already behavioral differences depending on whether the + * function is the caches etc. + * + * For correctness it'd be sufficient to set ->dropped to true. However, + * the accepted invalidation will commonly cause "low level" failures in + * PL code, with an OID in the error message. Making this harder to + * test... + */ + if (created_entry) { - /* First time through - initialize function stat table */ - HASHCTL hash_ctl; - - hash_ctl.keysize = sizeof(Oid); - hash_ctl.entrysize = sizeof(PgStat_BackendFunctionEntry); - pgStatFunctions = hash_create("Function stat entries", - PGSTAT_FUNCTION_HASH_SIZE, - &hash_ctl, - HASH_ELEM | HASH_BLOBS); + AcceptInvalidationMessages(); + if (!SearchSysCacheExists1(PROCOID, ObjectIdGetDatum(fcinfo->flinfo->fn_oid))) + { + pgstat_drop_entry(PGSTAT_KIND_FUNCTION, MyDatabaseId, + fcinfo->flinfo->fn_oid); + ereport(ERROR, errcode(ERRCODE_UNDEFINED_FUNCTION), + errmsg("function call to dropped function")); + } } - /* Get the stats entry for this function, create if necessary */ - htabent = hash_search(pgStatFunctions, &fcinfo->flinfo->fn_oid, - HASH_ENTER, &found); - if (!found) - MemSet(&htabent->f_counts, 0, sizeof(PgStat_FunctionCounts)); + pending = entry_ref->pending; - fcu->fs = &htabent->f_counts; + fcu->fs = &pending->f_counts; /* save stats for this function, later used to compensate for recursion */ - fcu->save_f_total_time = htabent->f_counts.f_total_time; + fcu->save_f_total_time = pending->f_counts.f_total_time; /* save current backend-wide total time */ fcu->save_total = total_func_time; @@ -167,64 +181,37 @@ pgstat_end_function_usage(PgStat_FunctionCallUsage *fcu, bool finalize) fs->f_numcalls++; fs->f_total_time = f_total; INSTR_TIME_ADD(fs->f_self_time, f_self); - - /* indicate that we have something to send */ - have_function_stats = true; } /* - * Subroutine for pgstat_report_stat: populate and send a function stat message + * Flush out pending stats for the entry + * + * If nowait is true, this function returns false if lock could not + * immediately acquired, otherwise true is returned. */ -void -pgstat_send_funcstats(void) +bool +pgstat_function_flush_cb(PgStat_EntryRef *entry_ref, bool nowait) { - /* we assume this inits to all zeroes: */ - static const PgStat_FunctionCounts all_zeroes; + PgStat_BackendFunctionEntry *localent; + PgStatShared_Function *shfuncent; - PgStat_MsgFuncstat msg; - PgStat_BackendFunctionEntry *entry; - HASH_SEQ_STATUS fstat; + localent = (PgStat_BackendFunctionEntry *) entry_ref->pending; + shfuncent = (PgStatShared_Function *) entry_ref->shared_stats; - if (pgStatFunctions == NULL) - return; - - pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_FUNCSTAT); - msg.m_databaseid = MyDatabaseId; - msg.m_nentries = 0; - - hash_seq_init(&fstat, pgStatFunctions); - while ((entry = (PgStat_BackendFunctionEntry *) hash_seq_search(&fstat)) != NULL) - { - PgStat_FunctionEntry *m_ent; + /* localent always has non-zero content */ - /* Skip it if no counts accumulated since last time */ - if (memcmp(&entry->f_counts, &all_zeroes, - sizeof(PgStat_FunctionCounts)) == 0) - continue; - - /* need to convert format of time accumulators */ - m_ent = &msg.m_entry[msg.m_nentries]; - m_ent->f_id = entry->f_id; - m_ent->f_numcalls = entry->f_counts.f_numcalls; - m_ent->f_total_time = INSTR_TIME_GET_MICROSEC(entry->f_counts.f_total_time); - m_ent->f_self_time = INSTR_TIME_GET_MICROSEC(entry->f_counts.f_self_time); - - if (++msg.m_nentries >= PGSTAT_NUM_FUNCENTRIES) - { - pgstat_send(&msg, offsetof(PgStat_MsgFuncstat, m_entry[0]) + - msg.m_nentries * sizeof(PgStat_FunctionEntry)); - msg.m_nentries = 0; - } + if (!pgstat_lock_entry(entry_ref, nowait)) + return false; - /* reset the entry's counts */ - MemSet(&entry->f_counts, 0, sizeof(PgStat_FunctionCounts)); - } + shfuncent->stats.f_numcalls += localent->f_counts.f_numcalls; + shfuncent->stats.f_total_time += + INSTR_TIME_GET_MICROSEC(localent->f_counts.f_total_time); + shfuncent->stats.f_self_time += + INSTR_TIME_GET_MICROSEC(localent->f_counts.f_self_time); - if (msg.m_nentries > 0) - pgstat_send(&msg, offsetof(PgStat_MsgFuncstat, m_entry[0]) + - msg.m_nentries * sizeof(PgStat_FunctionEntry)); + pgstat_unlock_entry(entry_ref); - have_function_stats = false; + return true; } /* @@ -235,12 +222,22 @@ pgstat_send_funcstats(void) PgStat_BackendFunctionEntry * find_funcstat_entry(Oid func_id) { - pgstat_assert_is_up(); + PgStat_EntryRef *entry_ref; - if (pgStatFunctions == NULL) - return NULL; + entry_ref = pgstat_fetch_pending_entry(PGSTAT_KIND_FUNCTION, MyDatabaseId, func_id); + + if (entry_ref) + return entry_ref->pending; + return NULL; +} - return (PgStat_BackendFunctionEntry *) hash_search(pgStatFunctions, - (void *) &func_id, - HASH_FIND, NULL); +/* + * Support function for the SQL-callable pgstat* functions. Returns + * the collected statistics for one function or NULL. + */ +PgStat_StatFuncEntry * +pgstat_fetch_stat_funcentry(Oid func_id) +{ + return (PgStat_StatFuncEntry *) + pgstat_fetch_entry(PGSTAT_KIND_FUNCTION, MyDatabaseId, func_id); } |