From f0029f1e410852b41b5562939051ede86235508b Mon Sep 17 00:00:00 2001 From: Melanie Plageman Date: Fri, 10 Mar 2023 18:33:47 -0500 Subject: [PATCH v4] vacuum reloads config file more often --- src/backend/commands/vacuum.c | 38 ++++++++++++---- src/backend/postmaster/autovacuum.c | 69 +++++++++++++++++++++++------ src/include/postmaster/autovacuum.h | 2 + 3 files changed, 87 insertions(+), 22 deletions(-) diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c index 2e12baf8eb..9d5ce846a5 100644 --- a/src/backend/commands/vacuum.c +++ b/src/backend/commands/vacuum.c @@ -48,6 +48,7 @@ #include "pgstat.h" #include "postmaster/autovacuum.h" #include "postmaster/bgworker_internals.h" +#include "postmaster/interrupt.h" #include "storage/bufmgr.h" #include "storage/lmgr.h" #include "storage/proc.h" @@ -75,6 +76,7 @@ int vacuum_multixact_failsafe_age; /* A few variables that don't seem worth passing around as parameters */ static MemoryContext vac_context = NULL; static BufferAccessStrategy vac_strategy; +static bool analyze_in_outer_xact = false; /* @@ -313,8 +315,7 @@ vacuum(List *relations, VacuumParams *params, static bool in_vacuum = false; const char *stmttype; - volatile bool in_outer_xact, - use_own_xacts; + volatile bool use_own_xacts; Assert(params != NULL); @@ -331,10 +332,10 @@ vacuum(List *relations, VacuumParams *params, if (params->options & VACOPT_VACUUM) { PreventInTransactionBlock(isTopLevel, stmttype); - in_outer_xact = false; + analyze_in_outer_xact = false; } else - in_outer_xact = IsInTransactionBlock(isTopLevel); + analyze_in_outer_xact = IsInTransactionBlock(isTopLevel); /* * Due to static variables vac_context, anl_context and vac_strategy, @@ -456,7 +457,7 @@ vacuum(List *relations, VacuumParams *params, Assert(params->options & VACOPT_ANALYZE); if (IsAutoVacuumWorkerProcess()) use_own_xacts = true; - else if (in_outer_xact) + else if (analyze_in_outer_xact) use_own_xacts = false; else if (list_length(relations) > 1) use_own_xacts = true; @@ -474,7 +475,7 @@ vacuum(List *relations, VacuumParams *params, */ if (use_own_xacts) { - Assert(!in_outer_xact); + Assert(!analyze_in_outer_xact); /* ActiveSnapshot is not set by autovacuum */ if (ActiveSnapshotSet()) @@ -526,7 +527,7 @@ vacuum(List *relations, VacuumParams *params, } analyze_rel(vrel->oid, vrel->relation, params, - vrel->va_cols, in_outer_xact, vac_strategy); + vrel->va_cols, analyze_in_outer_xact, vac_strategy); if (use_own_xacts) { @@ -549,6 +550,7 @@ vacuum(List *relations, VacuumParams *params, { in_vacuum = false; VacuumCostActive = false; + analyze_in_outer_xact = false; } PG_END_TRY(); @@ -2238,10 +2240,28 @@ vacuum_delay_point(void) WAIT_EVENT_VACUUM_DELAY); ResetLatch(MyLatch); + /* + * Reload the configuration file if requested. This allows changes to + * [autovacuum_]vacuum_cost_limit and [autovacuum_]vacuum_cost_delay + * to take effect while a table is being vacuumed or analyzed. + */ + if (ConfigReloadPending && !analyze_in_outer_xact) + { + ConfigReloadPending = false; + ProcessConfigFile(PGC_SIGHUP); + AutoVacuumUpdateDelay(); + } + VacuumCostBalance = 0; - /* update balance values for workers */ - AutoVacuumUpdateDelay(); + /* + * Update balance values for workers. We must always do this in case + * the autovacuum launcher has done a rebalance (as it does when + * launching a new worker). + */ + AutoVacuumUpdateLimit(); + + VacuumCostActive = (VacuumCostDelay > 0); /* Might have gotten an interrupt while sleeping */ CHECK_FOR_INTERRUPTS(); diff --git a/src/backend/postmaster/autovacuum.c b/src/backend/postmaster/autovacuum.c index c0e2e00a7e..7a202b2bd9 100644 --- a/src/backend/postmaster/autovacuum.c +++ b/src/backend/postmaster/autovacuum.c @@ -226,7 +226,7 @@ typedef struct WorkerInfoData bool wi_dobalance; bool wi_sharedrel; double wi_cost_delay; - int wi_cost_limit; + pg_atomic_uint32 wi_cost_limit; int wi_cost_limit_base; } WorkerInfoData; @@ -743,6 +743,7 @@ AutoVacLauncherMain(int argc, char *argv[]) worker = AutoVacuumShmem->av_startingWorker; worker->wi_dboid = InvalidOid; worker->wi_tableoid = InvalidOid; + pg_atomic_write_u32(&MyWorkerInfo->wi_cost_limit, 0); worker->wi_sharedrel = false; worker->wi_proc = NULL; worker->wi_launchtime = 0; @@ -1757,7 +1758,7 @@ FreeWorkerInfo(int code, Datum arg) MyWorkerInfo->wi_launchtime = 0; MyWorkerInfo->wi_dobalance = false; MyWorkerInfo->wi_cost_delay = 0; - MyWorkerInfo->wi_cost_limit = 0; + pg_atomic_write_u32(&MyWorkerInfo->wi_cost_limit, 0); MyWorkerInfo->wi_cost_limit_base = 0; dlist_push_head(&AutoVacuumShmem->av_freeWorkers, &MyWorkerInfo->wi_links); @@ -1780,11 +1781,36 @@ FreeWorkerInfo(int code, Datum arg) void AutoVacuumUpdateDelay(void) { - if (MyWorkerInfo) + if (!MyWorkerInfo) + return; + + LWLockAcquire(AutovacuumLock, LW_SHARED); + + if (MyWorkerInfo->wi_dobalance) { - VacuumCostDelay = MyWorkerInfo->wi_cost_delay; - VacuumCostLimit = MyWorkerInfo->wi_cost_limit; + VacuumCostDelay = autovacuum_vac_cost_delay >= 0 ? + autovacuum_vac_cost_delay : VacuumCostDelay; + + MyWorkerInfo->wi_cost_delay = VacuumCostDelay; } + else + VacuumCostDelay = MyWorkerInfo->wi_cost_delay; + + LWLockRelease(AutovacuumLock); + +} + +/* + * Helper for vacuum_delay_point() to allow workers to read their + * wi_cost_limit. + */ +void +AutoVacuumUpdateLimit(void) +{ + if (!MyWorkerInfo) + return; + + VacuumCostLimit = pg_atomic_read_u32(&MyWorkerInfo->wi_cost_limit); } /* @@ -1855,16 +1881,15 @@ autovac_balance_cost(void) * in these calculations, let's be sure we don't ever set * cost_limit to more than the base value. */ - worker->wi_cost_limit = Max(Min(limit, - worker->wi_cost_limit_base), - 1); + pg_atomic_unlocked_write_u32(&worker->wi_cost_limit, + Max(Min(limit, worker->wi_cost_limit_base), 1)); } if (worker->wi_proc != NULL) elog(DEBUG2, "autovac_balance_cost(pid=%d db=%u, rel=%u, dobalance=%s cost_limit=%d, cost_limit_base=%d, cost_delay=%g)", worker->wi_proc->pid, worker->wi_dboid, worker->wi_tableoid, worker->wi_dobalance ? "yes" : "no", - worker->wi_cost_limit, worker->wi_cost_limit_base, + pg_atomic_read_u32(&worker->wi_cost_limit), worker->wi_cost_limit_base, worker->wi_cost_delay); } } @@ -2326,6 +2351,13 @@ do_autovacuum(void) ConfigReloadPending = false; ProcessConfigFile(PGC_SIGHUP); + /* + * Autovacuum workers should always update VacuumCostDelay and + * VacuumCostLimit in case they were overridden by the reload. + */ + AutoVacuumUpdateDelay(); + AutoVacuumUpdateLimit(); + /* * You might be tempted to bail out if we see autovacuum is now * disabled. Must resist that temptation -- this might be a @@ -2424,21 +2456,22 @@ do_autovacuum(void) stdVacuumCostDelay = VacuumCostDelay; stdVacuumCostLimit = VacuumCostLimit; + /* Must hold AutovacuumLock while mucking with cost balance info */ LWLockAcquire(AutovacuumLock, LW_EXCLUSIVE); /* advertise my cost delay parameters for the balancing algorithm */ MyWorkerInfo->wi_dobalance = tab->at_dobalance; MyWorkerInfo->wi_cost_delay = tab->at_vacuum_cost_delay; - MyWorkerInfo->wi_cost_limit = tab->at_vacuum_cost_limit; + /* this cannot exceed 10000 anyway */ + pg_atomic_unlocked_write_u32(&MyWorkerInfo->wi_cost_limit, + tab->at_vacuum_cost_limit); MyWorkerInfo->wi_cost_limit_base = tab->at_vacuum_cost_limit; + AutoVacuumUpdateLimit(); /* do a balance */ autovac_balance_cost(); - /* set the active cost parameters from the result of that */ - AutoVacuumUpdateDelay(); - /* done */ LWLockRelease(AutovacuumLock); @@ -2569,6 +2602,8 @@ deleted: { ConfigReloadPending = false; ProcessConfigFile(PGC_SIGHUP); + AutoVacuumUpdateDelay(); + AutoVacuumUpdateLimit(); } LWLockAcquire(AutovacuumLock, LW_EXCLUSIVE); @@ -3361,6 +3396,7 @@ AutoVacuumShmemInit(void) { WorkerInfo worker; int i; + dlist_iter iter; Assert(!found); @@ -3374,10 +3410,17 @@ AutoVacuumShmemInit(void) worker = (WorkerInfo) ((char *) AutoVacuumShmem + MAXALIGN(sizeof(AutoVacuumShmemStruct))); + /* initialize the WorkerInfo free list */ for (i = 0; i < autovacuum_max_workers; i++) dlist_push_head(&AutoVacuumShmem->av_freeWorkers, &worker[i].wi_links); + + dlist_foreach(iter, &AutoVacuumShmem->av_freeWorkers) + pg_atomic_init_u32( + &(dlist_container(WorkerInfoData, wi_links, iter.cur))->wi_cost_limit, + 0); + } else Assert(found); diff --git a/src/include/postmaster/autovacuum.h b/src/include/postmaster/autovacuum.h index c140371b51..558358911c 100644 --- a/src/include/postmaster/autovacuum.h +++ b/src/include/postmaster/autovacuum.h @@ -66,6 +66,8 @@ extern void AutoVacWorkerFailed(void); /* autovacuum cost-delay balancer */ extern void AutoVacuumUpdateDelay(void); +extern void AutoVacuumUpdateLimit(void); + #ifdef EXEC_BACKEND extern void AutoVacLauncherMain(int argc, char *argv[]) pg_attribute_noreturn(); extern void AutoVacWorkerMain(int argc, char *argv[]) pg_attribute_noreturn(); -- 2.37.2