{"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","derived_content_hash":"0a35ceeb0b9054e82292dc8efb77b845b5f03ce0c6d17dbec59d5e0d3887e2f6","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."],"description_zh":"I/O 操作的上下文。可能的值有：\n\nnormal：某类 I/O 操作的默认或标准 context。例如，默认情况下关系数据会读入共享缓冲区并从共享缓冲区写出，因此关系数据与共享缓冲区之间的读写会在 context 为 normal 时跟踪。 init：创建 WAL 段时执行的 I/O 操作会在 context 为 init 时跟踪。 vacuum：对永久关系执行清理和分析时，在共享缓冲区之外执行的 I/O 操作。临时表清理与其他临时表 I/O 操作共用同一本地缓冲池，因此会在 context 为 normal 时跟踪。 bulkread：某些在共享缓冲区之外执行的大型读取 I/O 操作，例如对大表的顺序扫描。 bulkwrite：某些在共享缓冲区之外执行的大型写入 I/O 操作，例如 COPY。","description_zh_html":"\u003cp\u003epg_stat_io.context 统计字段。\u003c/p\u003e\u003cdl\u003e\u003cdt\u003e视图\u003c/dt\u003e\u003cdd\u003e\u003ccode\u003epg_stat_io\u003c/code\u003e\u003c/dd\u003e\u003cdt\u003e字段\u003c/dt\u003e\u003cdd\u003e\u003ccode\u003econtext\u003c/code\u003e\u003c/dd\u003e\u003cdt\u003eSQL 类型\u003c/dt\u003e\u003cdd\u003e\u003ccode\u003etext\u003c/code\u003e\u003c/dd\u003e\u003c/dl\u003e\u003ch3\u003e同版本中文手册定义\u003c/h3\u003e\u003cp\u003eI/O 操作的上下文。可能的值有：\n\nnormal：某类 I/O 操作的默认或标准 context。例如，默认情况下关系数据会读入共享缓冲区并从共享缓冲区写出，因此关系数据与共享缓冲区之间的读写会在 context 为 normal 时跟踪。 init：创建 WAL 段时执行的 I/O 操作会在 context 为 init 时跟踪。 vacuum：对永久关系执行清理和分析时，在共享缓冲区之外执行的 I/O 操作。临时表清理与其他临时表 I/O 操作共用同一本地缓冲池，因此会在 context 为 normal 时跟踪。 bulkread：某些在共享缓冲区之外执行的大型读取 I/O 操作，例如对大表的顺序扫描。 bulkwrite：某些在共享缓冲区之外执行的大型写入 I/O 操作，例如 COPY。\u003c/p\u003e\u003cp\u003e\u003ca href=\"/zh/docs/18/monitoring-stats.html#\"\u003e查看完整中文手册与上下文\u003c/a\u003e。\u003c/p\u003e","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."}],"facts_zh":[{"label":"视图","value":"pg_stat_io"},{"label":"字段","value":"context"},{"label":"SQL 类型","value":"text"},{"label":"字段定义记载的单位","value":"未指定"},{"label":"重置条件","value":"这些统计信息上次被重置的时间。"}],"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"}],"sections_zh":[{"paragraphs":["pg_stat_io 视图为后端类型、目标 I/O 对象和 I/O 上下文的每种组合提供一行，显示整个集群的 I/O 统计信息；无意义的组合会省略。目前跟踪关系（如表、索引）的 I/O 和 WAL 活动，但不跟踪绕过共享缓冲区的关系 I/O（例如将表从一个表空间移动到另一个表空间）。"],"title":"视图语义"},{"paragraphs":["重置范围和可见性请参阅下方同版本的统计信息收集与视图文档。不根据字段名称推断各字段的重置规则。"],"title":"采集与重置语义"},{"code":"SELECT context FROM pg_catalog.pg_stat_io;","paragraphs":["示例查询；不表示已执行，也不提供实测值。"],"title":"查看此字段"}],"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":[],"tables_zh":[],"units_mentioned":[],"view":"pg_stat_io","zh_from":{"authored_translation":"source-derived-structured-summary","body_sha256":"a5021a2943fd277bab7e2c61a836e11b1d673f5058b60e385c7b4046483aafb2","kind":"same-version-chinese-manual-with-source-derived-structured-summary","manual":{"anchor":"","build_id":107,"column":"context","extraction":"exact-catalog-field","locale":"zh-Hans","page_key":"monitoring-stats.html","source_hash":"0274aac7991450316bcf7be44635653b6d896fb00e321242c1b6674cb05c2e53","source_revision":"unknown:rendered-translation-baseline","translation_revision":"git:b1b500221dbe5437cfca004d6b04d3f6e422765d;html-sha256:08e987a66af27b98444a8057c256314eafa13611a3fb9e888214fc436824244b","url":"/zh/docs/18/monitoring-stats.html#","version":"18"},"runtime_rerun":false,"source_facts_revision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}},"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":"en","Fallback":false,"Versions":["16","17","18","19","20"],"Locales":["en","zh-Hans"],"Signatures":null,"Spellings":null,"SQLState":null,"Evidence":null}