{"Entry":{"collection":"metric","key":"pg_stat_io-context","name":"pg_stat_io.context","aliases":["context","pg_stat_io"],"metadata":{"aliases":["context","pg_stat_io"],"category":"pg_stat_io","content_hash":"03a1bec6b4d150a85efa4e0cb2aa1da3e2d64a686798d65dcc14f5ea49c0cc3c","imported_at":"2026-09-30T00:40:45.649455+08:00","name":"pg_stat_io.context","name_zh":"","slug":"pg_stat_io-context","summary":"The context of an I/O operation. Possible values are:\n\nnormal: The default or standard context for a type of I/O operation. For example, by default, relation data is read into and written out from shared buffers. Thus, reads and writes of relation data to and from shared buffers are tracked in context normal. init: I/O operations performed while creating the WAL segments are tracked in context init. vacuum: I/O operations performed outside of shared buffers while vacuuming and analyzing permanent relations. Temporary table vacuums use the same local buffer pool as other temporary table I/O operations and are tracked in context normal. bulkread: Certain large read I/O operations done outside of shared buffers, for example, a sequential scan of a large table. bulkwrite: Certain large write I/O operations done outside of shared buffers, such as COPY."}},"Definition":{"Collection":"metric","Key":"pg_stat_io-context","SourceDatabase":"center","Version":"18","SourceTable":"statistics_metric","SourceKey":"pg_stat_io-context","SourceRevision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","Facts":{"comparison_data":{"field":"context","sql_type":"text","units_mentioned":[],"view":"pg_stat_io"},"comparison_hash":"9b45bae767bdbc5ac5dbb33aeb424ef31004ac1e05f18d84666962894ca0b8fa","description":["The context of an I/O operation. Possible values are:\n\nnormal: The default or standard context for a type of I/O operation. For example, by default, relation data is read into and written out from shared buffers. Thus, reads and writes of relation data to and from shared buffers are tracked in context normal. init: I/O operations performed while creating the WAL segments are tracked in context init. vacuum: I/O operations performed outside of shared buffers while vacuuming and analyzing permanent relations. Temporary table vacuums use the same local buffer pool as other temporary table I/O operations and are tracked in context normal. bulkread: Certain large read I/O operations done outside of shared buffers, for example, a sequential scan of a large table. bulkwrite: Certain large write I/O operations done outside of shared buffers, such as COPY."],"documented":true,"facts":[{"label":"View","value":"pg_stat_io"},{"label":"Field","value":"context"},{"label":"SQL type","value":"text"},{"label":"Units named in the field definition","value":"Not specified"},{"label":"Reset observation","value":"Time at which these statistics were last reset."}],"field":"context","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 context FROM pg_catalog.pg_stat_io;","paragraphs":["Example query; no execution result or measured value is asserted."],"title":"Inspect this field"}],"signature":"SELECT context 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":"text","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-context","SourceDatabase":"center","Version":"18","Locale":"en","Title":"pg_stat_io.context","Summary":"The context of an I/O operation. Possible values are:\n\nnormal: The default or standard context for a type of I/O operation. For example, by default, relation data is read into and written out from shared buffers. Thus, reads and writes of relation data to and from shared buffers are tracked in context normal. init: I/O operations performed while creating the WAL segments are tracked in context init. vacuum: I/O operations performed outside of shared buffers while vacuuming and analyzing permanent relations. Temporary table vacuums use the same local buffer pool as other temporary table I/O operations and are tracked in context normal. bulkread: Certain large read I/O operations done outside of shared buffers, for example, a sequential scan of a large table. bulkwrite: Certain large write I/O operations done outside of shared buffers, such as COPY.","BodyHTML":"\u003cp\u003eThe context of an I/O operation. Possible values are:\n\nnormal: The default or standard context for a type of I/O operation. For example, by default, relation data is read into and written out from shared buffers. Thus, reads and writes of relation data to and from shared buffers are tracked in context normal. init: I/O operations performed while creating the WAL segments are tracked in context init. vacuum: I/O operations performed outside of shared buffers while vacuuming and analyzing permanent relations. Temporary table vacuums use the same local buffer pool as other temporary table I/O operations and are tracked in context normal. bulkread: Certain large read I/O operations done outside of shared buffers, for example, a sequential scan of a large table. bulkwrite: Certain large write I/O operations done outside of shared buffers, such as COPY.\u003c/p\u003e","SourceRevision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","ContentHash":"0316f972f4b31af9f49a36e870f43930f566917a968fa5401c6a343626cb3013","Payload":{"description":["The context of an I/O operation. Possible values are:\n\nnormal: The default or standard context for a type of I/O operation. For example, by default, relation data is read into and written out from shared buffers. Thus, reads and writes of relation data to and from shared buffers are tracked in context normal. init: I/O operations performed while creating the WAL segments are tracked in context init. vacuum: I/O operations performed outside of shared buffers while vacuuming and analyzing permanent relations. Temporary table vacuums use the same local buffer pool as other temporary table I/O operations and are tracked in context normal. bulkread: Certain large read I/O operations done outside of shared buffers, for example, a sequential scan of a large table. bulkwrite: Certain large write I/O operations done outside of shared buffers, such as COPY."],"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 context 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}