{"Entry":{"collection":"metric","key":"pg_stat_io-evictions","name":"pg_stat_io.evictions","aliases":["evictions","pg_stat_io"],"metadata":{"aliases":["evictions","pg_stat_io"],"category":"pg_stat_io","content_hash":"c98d573490e27cea4c89c7dc106d3e582f13660c149a423fbf3154c0dd83f94c","imported_at":"2026-09-30T00:40:45.651555+08:00","name":"pg_stat_io.evictions","name_zh":"","slug":"pg_stat_io-evictions","summary":"Number of times a block has been written out from a shared or local buffer in order to make it available for another use.\n\nIn context normal, this counts the number of times a block was evicted from a buffer and replaced with another block. In contexts bulkwrite, bulkread, and vacuum, this counts the number of times a block was evicted from shared buffers in order to add the shared buffer to a separate, size-limited ring buffer for use in a bulk I/O operation."}},"Definition":{"Collection":"metric","Key":"pg_stat_io-evictions","SourceDatabase":"center","Version":"18","SourceTable":"statistics_metric","SourceKey":"pg_stat_io-evictions","SourceRevision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","Facts":{"comparison_data":{"field":"evictions","sql_type":"bigint","units_mentioned":[],"view":"pg_stat_io"},"comparison_hash":"b80f04bcfc7e50095f41602dd67c1aad52a4b2a29183520ad91e977b087ef7b5","description":["Number of times a block has been written out from a shared or local buffer in order to make it available for another use.\n\nIn context normal, this counts the number of times a block was evicted from a buffer and replaced with another block. In contexts bulkwrite, bulkread, and vacuum, this counts the number of times a block was evicted from shared buffers in order to add the shared buffer to a separate, size-limited ring buffer for use in a bulk I/O operation."],"documented":true,"facts":[{"label":"View","value":"pg_stat_io"},{"label":"Field","value":"evictions"},{"label":"SQL type","value":"bigint"},{"label":"Units named in the field definition","value":"Not specified"},{"label":"Reset observation","value":"Time at which these statistics were last reset."}],"field":"evictions","manual_html":"","manual_path":"/docs/18/monitoring-stats.html","related":[{"label":"pg_stat_io columns","url":"/wiki/catalog/pg_stat_io/?v=18"},{"label":"Statistics collection and reset functions","url":"/docs/18/monitoring-stats.html"}],"release":{"channel":"stable","label":"18.6","major":"18","ref":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2","revision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"},"sections":[{"paragraphs":["The pg_stat_io view will contain one row for each combination of backend type, target I/O object, and I/O context, showing cluster-wide I/O statistics. Combinations which do not make sense are omitted.\n\nCurrently, I/O on relations (e.g. tables, indexes) and WAL activity are tracked. However, relation I/O which bypasses shared buffers (e.g. when moving a table from one tablespace to another) is currently not tracked."],"title":"View semantics"},{"paragraphs":["Read the same-version statistics collection and view documentation below for reset scope and visibility. No per-field reset rule is inferred from the field name."],"title":"Collection and reset context"},{"code":"SELECT evictions FROM pg_catalog.pg_stat_io;","paragraphs":["Example query; no execution result or measured value is asserted."],"title":"Inspect this field"}],"signature":"SELECT evictions FROM pg_catalog.pg_stat_io;","source_only":false,"sources":[{"label":"PostgreSQL 18 English manual","path":"monitoring-stats.html","sha256":"aa979eed08627fbf715a9d792094a162a73671db5af810f3ab2aad3e073d5722","url":"/docs/18/monitoring-stats.html#PG-STAT-IO-VIEW"}],"sql_type":"bigint","tables":[],"units_mentioned":[],"view":"pg_stat_io"},"ManualEvidence":{"manual_path":"/docs/18/monitoring-stats.html","release":{"channel":"stable","label":"18.6","major":"18","ref":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2","revision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"},"sources":[{"label":"PostgreSQL 18 English manual","path":"monitoring-stats.html","sha256":"aa979eed08627fbf715a9d792094a162a73671db5af810f3ab2aad3e073d5722","url":"/docs/18/monitoring-stats.html#PG-STAT-IO-VIEW"}]},"MeasuredEvidence":{}},"Text":{"Collection":"metric","Key":"pg_stat_io-evictions","SourceDatabase":"center","Version":"18","Locale":"en","Title":"pg_stat_io.evictions","Summary":"Number of times a block has been written out from a shared or local buffer in order to make it available for another use.\n\nIn context normal, this counts the number of times a block was evicted from a buffer and replaced with another block. In contexts bulkwrite, bulkread, and vacuum, this counts the number of times a block was evicted from shared buffers in order to add the shared buffer to a separate, size-limited ring buffer for use in a bulk I/O operation.","BodyHTML":"\u003cp\u003eNumber of times a block has been written out from a shared or local buffer in order to make it available for another use.\n\nIn context normal, this counts the number of times a block was evicted from a buffer and replaced with another block. In contexts bulkwrite, bulkread, and vacuum, this counts the number of times a block was evicted from shared buffers in order to add the shared buffer to a separate, size-limited ring buffer for use in a bulk I/O operation.\u003c/p\u003e","SourceRevision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","ContentHash":"895093d0c9b51b658f3b4edcb7c55fb3c3c271cb6a852357e0d32636d8505dee","Payload":{"description":["Number of times a block has been written out from a shared or local buffer in order to make it available for another use.\n\nIn context normal, this counts the number of times a block was evicted from a buffer and replaced with another block. In contexts bulkwrite, bulkread, and vacuum, this counts the number of times a block was evicted from shared buffers in order to add the shared buffer to a separate, size-limited ring buffer for use in a bulk I/O operation."],"manual_html":"","related":[{"label":"pg_stat_io columns","url":"/wiki/catalog/pg_stat_io/?v=18"},{"label":"Statistics collection and reset functions","url":"/docs/18/monitoring-stats.html"}],"sections":[{"paragraphs":["The pg_stat_io view will contain one row for each combination of backend type, target I/O object, and I/O context, showing cluster-wide I/O statistics. Combinations which do not make sense are omitted.\n\nCurrently, I/O on relations (e.g. tables, indexes) and WAL activity are tracked. However, relation I/O which bypasses shared buffers (e.g. when moving a table from one tablespace to another) is currently not tracked."],"title":"View semantics"},{"paragraphs":["Read the same-version statistics collection and view documentation below for reset scope and visibility. No per-field reset rule is inferred from the field name."],"title":"Collection and reset context"},{"code":"SELECT evictions FROM pg_catalog.pg_stat_io;","paragraphs":["Example query; no execution result or measured value is asserted."],"title":"Inspect this field"}],"tables":[]}},"RequestedLocale":"zh-Hans","Fallback":true,"Versions":["16","17","18","19","20"],"Locales":["en"],"Signatures":null,"Spellings":null,"SQLState":null,"Evidence":null}