From bab9269bde542fdfe82bce0171a5031a6c5afa83 Mon Sep 17 00:00:00 2001 From: Melanie Plageman Date: Sun, 19 Mar 2023 18:00:08 -0400 Subject: [PATCH v10 1/2] Add VACUUM BUFFER_USAGE_LIMIT option and GUC Add GUC, vacuum_buffer_usage_limit, and VACUUM option, BUFFER_USAGE_LIMIT, through which the user can specify the maximum size to use for buffers for VACUUM, ANALYZE, and autovacuum. The size is converted into a number of shared buffers which are tracked in a BufferAccessStrategyData object. The explicit VACUUM option, when specified, overrides the GUC value, unless it is specified as -1. Reviewed-by: David Rowley Reviewed-by: Justin Pryzby Discussion: https://www.postgresql.org/message-id/flat/20230111182720.ejifsclfwymw2reb%40awork3.anarazel.de --- doc/src/sgml/config.sgml | 30 ++++++ doc/src/sgml/ref/analyze.sgml | 26 ++++- doc/src/sgml/ref/vacuum.sgml | 22 +++++ src/backend/commands/vacuum.c | 85 +++++++++++++++- src/backend/commands/vacuumparallel.c | 14 ++- src/backend/postmaster/autovacuum.c | 19 +++- src/backend/storage/buffer/README | 4 + src/backend/storage/buffer/freelist.c | 98 +++++++++++++++++-- src/backend/utils/init/globals.c | 5 +- src/backend/utils/misc/guc_tables.c | 11 +++ src/backend/utils/misc/postgresql.conf.sample | 4 + src/bin/psql/tab-complete.c | 4 +- src/include/commands/vacuum.h | 6 ++ src/include/miscadmin.h | 2 + src/include/storage/bufmgr.h | 35 +++++++ src/include/utils/guc_hooks.h | 3 + src/test/regress/expected/vacuum.out | 4 + src/test/regress/sql/vacuum.sql | 3 + 18 files changed, 357 insertions(+), 18 deletions(-) diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index bcc49aec45..7e6af71af3 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -2001,6 +2001,36 @@ include_dir 'conf.d' + + + vacuum_buffer_usage_limit (integer) + + vacuum_buffer_usage_limit configuration parameter + + + + + Specifies the size of shared_buffers to be reused + for each backend participating in a given invocation of + VACUUM or ANALYZE or in + autovacuum. This size is converted to the number of shared buffers + which will be reused as part of a + Buffer Access Strategy. + 0 will disable use of a Buffer Access Strategy. + -1 will set the size to a default of + 256 KB. The maximum size is + 16 GB. The minimum size is the lesser + of 1/8 the size of shared buffers and 128 KB. The + default value is -1. If this value is specified + without units, it is taken as kilobytes. This parameter can be set at + any time. It can be overridden for + VACUUM and + ANALYZE + when passing the option. + + + + logical_decoding_work_mem (integer) diff --git a/doc/src/sgml/ref/analyze.sgml b/doc/src/sgml/ref/analyze.sgml index 2f94e89cb0..5b1fe1d860 100644 --- a/doc/src/sgml/ref/analyze.sgml +++ b/doc/src/sgml/ref/analyze.sgml @@ -28,6 +28,7 @@ ANALYZE [ VERBOSE ] [ table_and_columnsboolean ] SKIP_LOCKED [ boolean ] + BUFFER_USAGE_LIMIT [ string ] and table_and_columns is: @@ -51,9 +52,14 @@ ANALYZE [ VERBOSE ] [ table_and_columnstable_and_columns list, ANALYZE processes every table and materialized view in the current database that the current user has permission to analyze. - With a list, ANALYZE processes only those table(s). - It is further possible to give a list of column names for a table, - in which case only the statistics for those columns are collected. + With a list, ANALYZE processes only those table(s). It is + further possible to give a list of column names for a table, in which case + only the statistics for those columns are collected. + ANALYZE uses a + Buffer Access Strategy + when reading in the sample data. The number of buffers consumed for this can + be controlled by or by using + the option. @@ -95,6 +101,20 @@ ANALYZE [ VERBOSE ] [ table_and_columns + + BUFFER_USAGE_LIMIT + + + Specifies the + Buffer Access Strategy + ring buffer size for ANALYZE. See the + VACUUM option with + the same name. + + + + + boolean diff --git a/doc/src/sgml/ref/vacuum.sgml b/doc/src/sgml/ref/vacuum.sgml index b6d30b5764..7ebac56498 100644 --- a/doc/src/sgml/ref/vacuum.sgml +++ b/doc/src/sgml/ref/vacuum.sgml @@ -39,6 +39,7 @@ VACUUM [ FULL ] [ FREEZE ] [ VERBOSE ] [ ANALYZE ] [ integer SKIP_DATABASE_STATS [ boolean ] ONLY_DATABASE_STATS [ boolean ] + BUFFER_USAGE_LIMIT [ string ] and table_and_columns is: @@ -345,6 +346,27 @@ VACUUM [ FULL ] [ FREEZE ] [ VERBOSE ] [ ANALYZE ] [ Buffer Access Strategy + ring buffer size for VACUUM. This size is used to + calculate the number of shared buffers which will be reused as part of + this strategy. 0 disables use of a + Buffer Access Strategy. -1 + indicates that VACUUM should fall back to the value + specified by . + This option can't be used with the option or + option. If + is also specified, the + value is used for both the vacuum + and analyze stages. + + + + boolean diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c index da85330ef4..22365ee473 100644 --- a/src/backend/commands/vacuum.c +++ b/src/backend/commands/vacuum.c @@ -124,6 +124,9 @@ ExecVacuum(ParseState *pstate, VacuumStmt *vacstmt, bool isTopLevel) /* By default parallel vacuum is enabled */ params.nworkers = 0; + /* by default use buffer access strategy with default size */ + params.ring_size = -1; + /* Parse options list */ foreach(lc, vacstmt->options) { @@ -134,6 +137,65 @@ ExecVacuum(ParseState *pstate, VacuumStmt *vacstmt, bool isTopLevel) verbose = defGetBoolean(opt); else if (strcmp(opt->defname, "skip_locked") == 0) skip_locked = defGetBoolean(opt); + else if (strcmp(opt->defname, "buffer_usage_limit") == 0) + { + const char *hintmsg; + int result; + int sb_limit_kb; + char *vac_buffer_size; + int blcksz_kb = BLCKSZ / 1024; + + if (opt->arg == NULL) + { + ereport(ERROR, + (errcode(ERRCODE_SYNTAX_ERROR), + errmsg("buffer_usage_limit option requires a valid value"), + parser_errposition(pstate, opt->location))); + } + + vac_buffer_size = defGetString(opt); + + if (!parse_int(vac_buffer_size, &result, GUC_UNIT_KB, &hintmsg)) + { + ereport(ERROR, + (errcode(ERRCODE_INVALID_PARAMETER_VALUE), + errmsg("value: \"%s\": is invalid for buffer_usage_limit", + vac_buffer_size), + hintmsg ? errhint("%s", _(hintmsg)) : 0)); + } + + /* 0 and -1 are okay */ + if (result != -1 && result != 0) + { + sb_limit_kb = StrategyGetClampedBufsize(result); + + /* + * Check that specified size does not exceed allowed fraction + * of shared buffers. + */ + if (result != sb_limit_kb) + { + ereport(ERROR, + (errcode(ERRCODE_INVALID_PARAMETER_VALUE), + errmsg("buffer_usage_limit for vacuum cannot exceed %d KB because shared buffers is %d KB", + sb_limit_kb, NBuffers * blcksz_kb))); + } + + /* + * Check that specified size falls within the hard upper and + * lower limits. + */ + if (result < MIN_BAS_RING_SIZE_KB || result > MAX_BAS_RING_SIZE_KB) + { + ereport(ERROR, + (errcode(ERRCODE_INVALID_PARAMETER_VALUE), + errmsg("buffer_usage_limit for a vacuum must be between %d KB and %d KB", + MIN_BAS_RING_SIZE_KB, MAX_BAS_RING_SIZE_KB))); + } + } + + params.ring_size = result; + } else if (!vacstmt->is_vacuumcmd) ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), @@ -238,6 +300,16 @@ ExecVacuum(ParseState *pstate, VacuumStmt *vacstmt, bool isTopLevel) (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("VACUUM FULL cannot be performed in parallel"))); + if ((params.options & VACOPT_FULL) && params.ring_size > -1) + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("BUFFER_USAGE_LIMIT cannot be specified for VACUUM FULL"))); + + if ((params.options & VACOPT_ONLY_DATABASE_STATS) && params.ring_size > -1) + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("BUFFER_USAGE_LIMIT cannot be specified for VACUUM ONLY_DATABASE_STATS"))); + /* * Make sure VACOPT_ANALYZE is specified if any column lists are present. */ @@ -401,7 +473,18 @@ vacuum(List *relations, VacuumParams *params, { MemoryContext old_context = MemoryContextSwitchTo(vac_context); - bstrategy = GetAccessStrategy(BAS_VACUUM); + Assert(params->ring_size >= -1); + + if (params->ring_size == -1) + { + if (VacuumBufferUsageLimit == -1) + bstrategy = GetAccessStrategy(BAS_VACUUM); + else + bstrategy = GetAccessStrategyWithSize(BAS_VACUUM, VacuumBufferUsageLimit); + } + else + bstrategy = GetAccessStrategyWithSize(BAS_VACUUM, params->ring_size); + MemoryContextSwitchTo(old_context); } diff --git a/src/backend/commands/vacuumparallel.c b/src/backend/commands/vacuumparallel.c index 563117a8f6..614a35779a 100644 --- a/src/backend/commands/vacuumparallel.c +++ b/src/backend/commands/vacuumparallel.c @@ -87,6 +87,12 @@ typedef struct PVShared */ int maintenance_work_mem_worker; + /* + * The number of buffers each worker's Buffer Access Strategy ring should + * contain. + */ + int ring_nbuffers; + /* * Shared vacuum cost balance. During parallel vacuum, * VacuumSharedCostBalance points to this value and it accumulates the @@ -365,6 +371,9 @@ parallel_vacuum_init(Relation rel, Relation *indrels, int nindexes, maintenance_work_mem / Min(parallel_workers, nindexes_mwm) : maintenance_work_mem; + /* Use the same buffer size for all workers */ + shared->ring_nbuffers = StrategyGetBufferCount(bstrategy); + pg_atomic_init_u32(&(shared->cost_balance), 0); pg_atomic_init_u32(&(shared->active_nworkers), 0); pg_atomic_init_u32(&(shared->idx), 0); @@ -1018,8 +1027,9 @@ parallel_vacuum_main(dsm_segment *seg, shm_toc *toc) pvs.indname = NULL; pvs.status = PARALLEL_INDVAC_STATUS_INITIAL; - /* Each parallel VACUUM worker gets its own access strategy */ - pvs.bstrategy = GetAccessStrategy(BAS_VACUUM); + /* Each parallel VACUUM worker gets its own access strategy. */ + pvs.bstrategy = GetAccessStrategyWithSize(BAS_VACUUM, + shared->ring_nbuffers * (BLCKSZ / 1024)); /* Setup error traceback support for ereport() */ errcallback.callback = parallel_vacuum_error_callback; diff --git a/src/backend/postmaster/autovacuum.c b/src/backend/postmaster/autovacuum.c index 585d28148c..9b5ee32cb0 100644 --- a/src/backend/postmaster/autovacuum.c +++ b/src/backend/postmaster/autovacuum.c @@ -2290,9 +2290,15 @@ do_autovacuum(void) /* * Create a buffer access strategy object for VACUUM to use. We want to * use the same one across all the vacuum operations we perform, since the - * point is for VACUUM not to blow out the shared cache. + * point is for VACUUM not to blow out the shared cache. If we later enter + * failsafe mode, we will cease use of the BufferAccessStrategy. Either + * way, we clean up the BufferAccessStrategy object at the end of this + * function. */ - bstrategy = GetAccessStrategy(BAS_VACUUM); + if (VacuumBufferUsageLimit == -1) + bstrategy = GetAccessStrategy(BAS_VACUUM); + else + bstrategy = GetAccessStrategyWithSize(BAS_VACUUM, VacuumBufferUsageLimit); /* * create a memory context to act as fake PortalContext, so that the @@ -2884,6 +2890,15 @@ table_recheck_autovac(Oid relid, HTAB *table_toast_map, tab->at_params.multixact_freeze_table_age = multixact_freeze_table_age; tab->at_params.is_wraparound = wraparound; tab->at_params.log_min_duration = log_min_duration; + + /* + * TODO: should this be 0 so that we are sure that vacuum() never + * allocates a new bstrategy for us, even if we pass in NULL for that + * parameter? maybe could change how failsafe NULLs out bstrategy if + * so? + */ + tab->at_params.ring_size = VacuumBufferUsageLimit; + tab->at_vacuum_cost_limit = vac_cost_limit; tab->at_vacuum_cost_delay = vac_cost_delay; tab->at_relname = NULL; diff --git a/src/backend/storage/buffer/README b/src/backend/storage/buffer/README index a775276ff2..d7c9d99af2 100644 --- a/src/backend/storage/buffer/README +++ b/src/backend/storage/buffer/README @@ -236,6 +236,10 @@ buffers were sent to the freelist, which was effectively a buffer ring of 1 buffer, resulting in excessive WAL flushing. Allowing VACUUM to update 256KB between WAL flushes should be more efficient. +In v16, the 256KB ring was made configurable by way of the +vacuum_buffer_usage_limit GUC and the BUFFER_USAGE_LIMIT option to VACUUM and +ANALYZE. + Bulk writes work similarly to VACUUM. Currently this applies only to COPY IN and CREATE TABLE AS SELECT. (Might it be interesting to make seqscan UPDATE and DELETE use the bulkwrite strategy?) For bulk writes diff --git a/src/backend/storage/buffer/freelist.c b/src/backend/storage/buffer/freelist.c index f122709fbe..ae777e9cd5 100644 --- a/src/backend/storage/buffer/freelist.c +++ b/src/backend/storage/buffer/freelist.c @@ -20,6 +20,7 @@ #include "storage/buf_internals.h" #include "storage/bufmgr.h" #include "storage/proc.h" +#include "utils/guc_hooks.h" #define INT_ACCESS_ONCE(var) ((int)(*((volatile int *)&(var)))) @@ -531,6 +532,42 @@ StrategyInitialize(bool init) * ---------------------------------------------------------------- */ +/* + * GUC check function to ensure GUC value specified is within the allowable + * range. This should match the checking in ExecVacuum(). + */ +bool +check_vacuum_buffer_usage_limit(int *newval, void **extra, + GucSource source) +{ + int sb_limit_kb; + + int blcksz_kb = BLCKSZ / 1024; + + /* Allow specifying the default or disabling Buffer Access Strategy */ + if (*newval == -1 || *newval == 0) + return true; + + /* Make sure ring isn't an undue fraction of shared buffers */ + sb_limit_kb = StrategyGetClampedBufsize(*newval); + + if (*newval != sb_limit_kb) + { + GUC_check_errdetail("\"vacuum_buffer_usage_limit\" value cannot exceed %d KB because shared_buffers is %d KB", + sb_limit_kb, NBuffers * blcksz_kb); + return false; + } + + /* Value upper and lower hard limits are inclusive */ + if (*newval >= MIN_BAS_RING_SIZE_KB && *newval <= MAX_BAS_RING_SIZE_KB) + return true; + + /* Value does not fall within any allowable range */ + GUC_check_errdetail("\"vacuum_buffer_usage_limit\" must be between %d KB and %d KB", + MIN_BAS_RING_SIZE_KB, MAX_BAS_RING_SIZE_KB); + + return false; +} /* * GetAccessStrategy -- create a BufferAccessStrategy object @@ -540,8 +577,7 @@ StrategyInitialize(bool init) BufferAccessStrategy GetAccessStrategy(BufferAccessStrategyType btype) { - BufferAccessStrategy strategy; - int nbuffers; + int ring_size_kb; /* * Select ring size to use. See buffer/README for rationales. @@ -556,13 +592,13 @@ GetAccessStrategy(BufferAccessStrategyType btype) return NULL; case BAS_BULKREAD: - nbuffers = 256 * 1024 / BLCKSZ; + ring_size_kb = 256; break; case BAS_BULKWRITE: - nbuffers = 16 * 1024 * 1024 / BLCKSZ; + ring_size_kb = 16 * 1024; break; case BAS_VACUUM: - nbuffers = 256 * 1024 / BLCKSZ; + ring_size_kb = 256; break; default: @@ -571,8 +607,45 @@ GetAccessStrategy(BufferAccessStrategyType btype) return NULL; /* keep compiler quiet */ } - /* Make sure ring isn't an undue fraction of shared buffers */ - nbuffers = Min(NBuffers / 8, nbuffers); + + return GetAccessStrategyWithSize(btype, + StrategyGetClampedBufsize(ring_size_kb)); +} + + +/* + * Helper to convert a size to a number of buffers. + */ +static inline int +bufsize_limit_to_nbuffers(int bufsize_limit_kb) +{ + int blcksz_kb = BLCKSZ / 1024; + + Assert(blcksz_kb > 0); + + return bufsize_limit_kb / blcksz_kb; +} + +/* + * GetAccessStrategyWithSize -- create a BufferAccessStrategy object with a + * number of buffers equivalent to the passed in size + */ +BufferAccessStrategy +GetAccessStrategyWithSize(BufferAccessStrategyType btype, int ring_size_kb) +{ + int nbuffers; + BufferAccessStrategy strategy; + + /* Default nbuffers should have resulted in calling GetAccessStrategy() */ + Assert(ring_size_kb >= 0); + + if (ring_size_kb == 0) + return NULL; + + nbuffers = bufsize_limit_to_nbuffers(ring_size_kb); + + Assert(nbuffers <= NBuffers / 8 && + nbuffers > 0); /* Allocate the object and initialize all elements to zeroes */ strategy = (BufferAccessStrategy) @@ -586,6 +659,17 @@ GetAccessStrategy(BufferAccessStrategyType btype) return strategy; } + +/* + * StrategyGetBufferCount -- an accessor for the number of buffers in the ring + */ +int +StrategyGetBufferCount(BufferAccessStrategy strategy) +{ + return strategy->nbuffers; +} + + /* * FreeAccessStrategy -- release a BufferAccessStrategy object * diff --git a/src/backend/utils/init/globals.c b/src/backend/utils/init/globals.c index 1b1d814254..059a097bef 100644 --- a/src/backend/utils/init/globals.c +++ b/src/backend/utils/init/globals.c @@ -139,7 +139,10 @@ int max_worker_processes = 8; int max_parallel_workers = 8; int MaxBackends = 0; -int VacuumCostPageHit = 1; /* GUC parameters for vacuum */ +/* GUC parameters for vacuum */ +int VacuumBufferUsageLimit = -1; + +int VacuumCostPageHit = 1; int VacuumCostPageMiss = 2; int VacuumCostPageDirty = 20; int VacuumCostLimit = 200; diff --git a/src/backend/utils/misc/guc_tables.c b/src/backend/utils/misc/guc_tables.c index 8062589efd..75e67cd74c 100644 --- a/src/backend/utils/misc/guc_tables.c +++ b/src/backend/utils/misc/guc_tables.c @@ -2224,6 +2224,17 @@ struct config_int ConfigureNamesInt[] = NULL, NULL, NULL }, + { + {"vacuum_buffer_usage_limit", PGC_USERSET, RESOURCES_MEM, + gettext_noop("Sets the buffer pool size for VACUUM, ANALYZE, and autovacuum."), + NULL, + GUC_UNIT_KB + }, + &VacuumBufferUsageLimit, + -1, -1, MAX_BAS_RING_SIZE_KB, + check_vacuum_buffer_usage_limit, NULL, NULL + }, + { {"shared_memory_size", PGC_INTERNAL, PRESET_OPTIONS, gettext_noop("Shows the size of the server's main shared memory area (rounded up to the nearest MB)."), diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index ee49ca3937..b962f500dc 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -157,6 +157,10 @@ # mmap # (change requires restart) #min_dynamic_shared_memory = 0MB # (change requires restart) +#vacuum_buffer_usage_limit = -1 # size of vacuum and analyze buffer access strategy ring. + # -1 to use default, + # 0 to disable vacuum buffer access strategy + # > 0 to specify size # - Disk - diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c index e38a49e8bd..6614fd2e62 100644 --- a/src/bin/psql/tab-complete.c +++ b/src/bin/psql/tab-complete.c @@ -2662,7 +2662,7 @@ psql_completion(const char *text, int start, int end) * one word, so the above test is correct. */ if (ends_with(prev_wd, '(') || ends_with(prev_wd, ',')) - COMPLETE_WITH("VERBOSE", "SKIP_LOCKED"); + COMPLETE_WITH("VERBOSE", "SKIP_LOCKED", "BUFFER_USAGE_LIMIT"); else if (TailMatches("VERBOSE|SKIP_LOCKED")) COMPLETE_WITH("ON", "OFF"); } @@ -4620,7 +4620,7 @@ psql_completion(const char *text, int start, int end) "DISABLE_PAGE_SKIPPING", "SKIP_LOCKED", "INDEX_CLEANUP", "PROCESS_MAIN", "PROCESS_TOAST", "TRUNCATE", "PARALLEL", "SKIP_DATABASE_STATS", - "ONLY_DATABASE_STATS"); + "ONLY_DATABASE_STATS", "BUFFER_USAGE_LIMIT"); else if (TailMatches("FULL|FREEZE|ANALYZE|VERBOSE|DISABLE_PAGE_SKIPPING|SKIP_LOCKED|PROCESS_MAIN|PROCESS_TOAST|TRUNCATE|SKIP_DATABASE_STATS|ONLY_DATABASE_STATS")) COMPLETE_WITH("ON", "OFF"); else if (TailMatches("INDEX_CLEANUP")) diff --git a/src/include/commands/vacuum.h b/src/include/commands/vacuum.h index bdfd96cfec..2ee5147e97 100644 --- a/src/include/commands/vacuum.h +++ b/src/include/commands/vacuum.h @@ -236,6 +236,12 @@ typedef struct VacuumParams * disabled. */ int nworkers; + + /* + * The size in KB of the Buffer Access Strategy ring to be used for VACUUM + * and ANALYZE. + */ + int ring_size; } VacuumParams; /* diff --git a/src/include/miscadmin.h b/src/include/miscadmin.h index 06a86f9ac1..03f4786fb2 100644 --- a/src/include/miscadmin.h +++ b/src/include/miscadmin.h @@ -263,6 +263,8 @@ extern PGDLLIMPORT double hash_mem_multiplier; extern PGDLLIMPORT int maintenance_work_mem; extern PGDLLIMPORT int max_parallel_maintenance_workers; +extern PGDLLIMPORT int VacuumBufferUsageLimit; + extern PGDLLIMPORT int VacuumCostPageHit; extern PGDLLIMPORT int VacuumCostPageMiss; extern PGDLLIMPORT int VacuumCostPageDirty; diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h index 73762cb1ec..f3a12b9277 100644 --- a/src/include/storage/bufmgr.h +++ b/src/include/storage/bufmgr.h @@ -101,6 +101,14 @@ extern PGDLLIMPORT int32 *LocalRefCount; /* upper limit for effective_io_concurrency */ #define MAX_IO_CONCURRENCY 1000 +/* + * Upper and lower hard limits for the Buffer Access Strategy ring size + * specified by the vacuum_buffer_usage_limit GUC and BUFFER_USAGE_LIMIT option + * to VACUUM and ANALYZE. + */ +#define MAX_BAS_RING_SIZE_KB (16 * 1024 * 1024) +#define MIN_BAS_RING_SIZE_KB 128 + /* special block number for ReadBuffer() */ #define P_NEW InvalidBlockNumber /* grow the file to get a new page */ @@ -194,7 +202,13 @@ extern Size BufferShmemSize(void); extern void AtProcExit_LocalBuffers(void); /* in freelist.c */ + extern BufferAccessStrategy GetAccessStrategy(BufferAccessStrategyType btype); +extern BufferAccessStrategy GetAccessStrategyWithSize( + BufferAccessStrategyType btype, + int ring_size_kb); +extern int StrategyGetBufferCount(BufferAccessStrategy strategy); + extern void FreeAccessStrategy(BufferAccessStrategy strategy); @@ -286,6 +300,27 @@ BufferGetPage(Buffer buffer) return (Page) BufferGetBlock(buffer); } +/* + * StrategyGetClampedBufsize + * Returns a clamped buffer size in KB + * + * Buffer Access Strategies should not consume more than the 1/8 of shared + * buffers. Given a size in KB, this helper calculates an acceptable clamped + * value, given the current size of shared buffers. + */ +static inline int +StrategyGetClampedBufsize(int bufsize_kb) +{ + int sb_limit_kb; + int blcksz_kb = BLCKSZ / 1024; + + Assert(blcksz_kb > 0); + + sb_limit_kb = NBuffers / 8 * blcksz_kb; + + return Min(sb_limit_kb, bufsize_kb); +} + /* * Check whether the given snapshot is too old to have safely read the given * page from the given table. If so, throw a "snapshot too old" error. diff --git a/src/include/utils/guc_hooks.h b/src/include/utils/guc_hooks.h index aeb3663071..1893292634 100644 --- a/src/include/utils/guc_hooks.h +++ b/src/include/utils/guc_hooks.h @@ -33,6 +33,9 @@ extern bool check_autovacuum_max_workers(int *newval, void **extra, GucSource source); extern bool check_autovacuum_work_mem(int *newval, void **extra, GucSource source); + +extern bool check_vacuum_buffer_usage_limit(int *newval, void **extra, + GucSource source); extern bool check_backtrace_functions(char **newval, void **extra, GucSource source); extern void assign_backtrace_functions(const char *newval, void *extra); diff --git a/src/test/regress/expected/vacuum.out b/src/test/regress/expected/vacuum.out index e5a312182e..fe675c5a2e 100644 --- a/src/test/regress/expected/vacuum.out +++ b/src/test/regress/expected/vacuum.out @@ -350,6 +350,10 @@ SELECT t.relfilenode = :toast_filenode AS is_same_toast_filenode f (1 row) +-- BUFFER_USAGE_LIMIT integer overflow error +VACUUM (BUFFER_USAGE_LIMIT 10000000000) vac_option_tab; +ERROR: value: "10000000000": is invalid for buffer_usage_limit +HINT: Value exceeds integer range. -- SKIP_DATABASE_STATS option VACUUM (SKIP_DATABASE_STATS) vactst; -- ONLY_DATABASE_STATS option diff --git a/src/test/regress/sql/vacuum.sql b/src/test/regress/sql/vacuum.sql index a1fad43657..fc068b7705 100644 --- a/src/test/regress/sql/vacuum.sql +++ b/src/test/regress/sql/vacuum.sql @@ -272,6 +272,9 @@ SELECT t.relfilenode = :toast_filenode AS is_same_toast_filenode FROM pg_class c, pg_class t WHERE c.reltoastrelid = t.oid AND c.relname = 'vac_option_tab'; +-- BUFFER_USAGE_LIMIT integer overflow error +VACUUM (BUFFER_USAGE_LIMIT 10000000000) vac_option_tab; + -- SKIP_DATABASE_STATS option VACUUM (SKIP_DATABASE_STATS) vactst; -- 2.37.2