{"Entry":{"collection":"guc","key":"autovacuum_vacuum_threshold","name":"autovacuum_vacuum_threshold","aliases":[],"metadata":{"baseline":false,"boot_human":"Not specified","boot_val":null,"category":"Vacuuming / Automatic Vacuuming","category_zh":"","changed_in":["18"],"changes":[{"documentation_changed":false,"fields":{},"from":"8.0","status":"added","to":"8.1"},{"documentation_changed":true,"fields":{},"from":"8.1","status":"changed","to":"8.2"},{"documentation_changed":true,"fields":{},"from":"8.2","status":"changed","to":"8.3"},{"documentation_changed":true,"fields":{},"from":"8.3","status":"changed","to":"8.4"},{"documentation_changed":true,"fields":{},"from":"9.4","status":"changed","to":"9.5"},{"documentation_changed":false,"fields":{"category":{"from":"Autovacuum","to":"Vacuuming / Automatic Vacuuming"}},"from":"17","status":"changed","to":"18"}],"content_hash":"ff737200cbf48f27566e11bb3d51128be1a5caed78e81da79e0290a50bd03a3f","context":"","default_changed_in":[],"default_history":[{"from":"9.0","to":"19","value":"50"}],"editorial":{"advice":{"olap":"Run explicit ANALYZE/VACUUM after bulk loads instead of waiting only for proportional triggers; plan freezing and visibility-map advancement separately for append-only partitions.","oltp":"Tune autovacuum_vacuum_threshold from table size, change rate, and maintenance SLA, using per-table thresholds for large/hot relations. Observe trigger intervals, dead tuples, and ANALYZE/VACUUM duration.","small":"Start with upstream. Fixed thresholds dominate on small tables; after changes, confirm worker and I/O headroom."},"mechanism":["Minimum number of tuple updates or deletes prior to vacuum. A configuration reload applies a new value; existing work already in flight is not retroactively changed.","The ordinary automatic-vacuum threshold is the base term plus scale factor times reltuples, capped by autovacuum_vacuum_max_threshold from PG18. It reacts to dead tuples from updates/deletes, permits per-table overrides, and is separate from mandatory anti-wraparound vacuuming.","Monitor and change autovacuum_vacuum_threshold together with autovacuum_vacuum_scale_factor, autovacuum_vacuum_max_threshold, autovacuum_vacuum_insert_threshold. Validate on the relevant server role and real workload, then use its sighup context to choose session change, reload, or restart; a historical boot default is not the current effective value."],"pitfalls":["Changing the global value while a table storage parameter overrides it.","Treating reltuples and cumulative change statistics as exact real-time counts.","Blaming a threshold without checking long transactions, replication slots, and worker saturation.","Buying short-term quiet by deferring maintenance until wraparound failsafe activates."],"references":[{"title":"PostgreSQL 19 Beta 4: autovacuum_vacuum_threshold","url":"https://www.postgresql.org/docs/19/runtime-config-vacuum.html#GUC-AUTOVACUUM-VACUUM-THRESHOLD"},{"title":"PostgreSQL 19 release notes","url":"https://www.postgresql.org/docs/19/release-19.html"}],"related":["autovacuum_vacuum_scale_factor","autovacuum_vacuum_max_threshold","autovacuum_vacuum_insert_threshold","autovacuum_vacuum_insert_scale_factor","autovacuum","autovacuum_analyze_scale_factor"],"summary":"autovacuum_vacuum_threshold — Minimum number of tuple updates or deletes prior to vacuum. Observed in PG9.0–19 Beta 4; its last measured boot default is 50 in PG19 Beta 4, with sighup context. This is a beta-snapshot fact and can change before PostgreSQL 19 GA."},"enumvals":[],"first_version":"8.1","group":"Vacuuming","group_slug":"vacuum","imported_at":"2026-09-27T17:57:30.845694+08:00","intro_commit":{},"key":"autovacuum_vacuum_threshold","last_version":"20","max_val":"","min_val":"","name":"autovacuum_vacuum_threshold","position":35,"present_in":["8.1","8.2","8.3","8.4","9.0","9.1","9.2","9.3","9.4","9.5","9.6","10","11","12","13","14","15","16","17","18","19","20"],"short_desc":"Specifies the minimum number of updated or deleted tuples needed to trigger a VACUUM in any one table.","short_desc_zh":"","source_rev":"english-manuals:0bf2afb09d5f9c1977a07f33323a044ba66d4c4fda35d179f828b4574aae3346","unit":"","vartype":"integer"}},"Definition":{"Collection":"guc","Key":"autovacuum_vacuum_threshold","SourceDatabase":"center","Version":"18","SourceTable":"guc","SourceKey":"autovacuum_vacuum_threshold","SourceRevision":"english-manuals:0bf2afb09d5f9c1977a07f33323a044ba66d4c4fda35d179f828b4574aae3346","Facts":{"boot_val":"50","category":"Vacuuming / Automatic Vacuuming","context":"sighup","description":"Specifies the minimum number of updated or deleted tuples needed to trigger a VACUUM in any one table. The default is 50 tuples. This parameter can only be set in the postgresql.conf file or on the server command line; but the setting can be overridden for individual tables by changing table storage parameters.","doc":{"anchor":"GUC-AUTOVACUUM-VACUUM-THRESHOLD","file":"runtime-config-vacuum.html","lang":"en","sha256":"7047f1fa9138b97f1812532f8a905fa7479451dfd64655e029a7d387b20b22e4","slug":"18"},"documented":true,"enumvals":null,"extra_desc":null,"lang":"en","max_val":"2147483647","metadata_version":"18","min_val":"0","name":"autovacuum_vacuum_threshold","short_desc":"Minimum number of tuple updates or deletes prior to vacuum.","source":"pg-settings-source-snapshot","unit":null,"vartype":"integer"},"ManualEvidence":{"doc":{"anchor":"GUC-AUTOVACUUM-VACUUM-THRESHOLD","file":"runtime-config-vacuum.html","lang":"en","sha256":"7047f1fa9138b97f1812532f8a905fa7479451dfd64655e029a7d387b20b22e4","slug":"18"}},"MeasuredEvidence":{"metadata_version":"18"}},"Text":{"Collection":"guc","Key":"autovacuum_vacuum_threshold","SourceDatabase":"center","Version":"18","Locale":"en","Title":"autovacuum_vacuum_threshold","Summary":"Specifies the minimum number of updated or deleted tuples needed to trigger a VACUUM in any one table. The default is 50 tuples. This parameter can only be set in the postgresql.conf file or on the server command line; but the setting can be overridden for individual tables by changing table storage parameters.","BodyHTML":"\u003cp\u003eSpecifies the minimum number of updated or deleted tuples needed to trigger a VACUUM in any one table. The default is 50 tuples. This parameter can only be set in the postgresql.conf file or on the server command line; but the setting can be overridden for individual tables by changing table storage parameters.\u003c/p\u003e","SourceRevision":"english-manuals:0bf2afb09d5f9c1977a07f33323a044ba66d4c4fda35d179f828b4574aae3346","ContentHash":"489c4342d567a16c80cac5e295112a468df5fcb51559e413daa1097a5a159d3f","Payload":{"description":"Specifies the minimum number of updated or deleted tuples needed to trigger a VACUUM in any one table. The default is 50 tuples. This parameter can only be set in the postgresql.conf file or on the server command line; but the setting can be overridden for individual tables by changing table storage parameters."}},"RequestedLocale":"zh-Hans","Fallback":true,"Versions":["10","11","12","13","14","15","16","17","18","19","20","8.1","8.2","8.3","8.4","9.0","9.1","9.2","9.3","9.4","9.5","9.6"],"Locales":["en"],"Signatures":null,"Spellings":null,"SQLState":null,"Evidence":null}