{"Entry":{"collection":"metric","key":"pg_stat_replication-write_lag","name":"pg_stat_replication.write_lag","aliases":["write_lag","pg_stat_replication"],"metadata":{"aliases":["write_lag","pg_stat_replication"],"category":"pg_stat_replication","content_hash":"4356b7796242ca6b0fe42efc443a54984c24f3ec81503994510777df98a0b3cb","derived_content_hash":"ea4b54f45c3ccae8b712767dbd281db4cb5044a9c8f7184e92329ed672efd4bc","imported_at":"2026-09-30T00:40:46.103012+08:00","name":"pg_stat_replication.write_lag","name_zh":"","slug":"pg_stat_replication-write_lag","summary":"Time elapsed between flushing recent WAL locally and receiving notification that this standby server has written it (but not yet flushed it or applied it). This can be used to gauge the delay that synchronous_commit level remote_write incurred while committing if this server was configured as a synchronous standby."}},"Definition":{"Collection":"metric","Key":"pg_stat_replication-write_lag","SourceDatabase":"center","Version":"18","SourceTable":"statistics_metric","SourceKey":"pg_stat_replication-write_lag","SourceRevision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","Facts":{"comparison_data":{"field":"write_lag","sql_type":"interval","units_mentioned":[],"view":"pg_stat_replication"},"comparison_hash":"d6602b503a844e3164b075d09039d89e75b946f36b6b08908230bc2766e11332","description":["Time elapsed between flushing recent WAL locally and receiving notification that this standby server has written it (but not yet flushed it or applied it). This can be used to gauge the delay that synchronous_commit level remote_write incurred while committing if this server was configured as a synchronous standby."],"description_zh":"从在本地将最近的 WAL 刷盘，到收到该备库已写入该 WAL（但尚未刷盘或应用）的通知之间经过的时间。如果该服务器被配置为同步备库，可用此值衡量在提交时 synchronous_commit 级别 remote_write 所导致的延迟。","description_zh_html":"\u003cp\u003epg_stat_replication.write_lag 统计字段。\u003c/p\u003e\u003cdl\u003e\u003cdt\u003e视图\u003c/dt\u003e\u003cdd\u003e\u003ccode\u003epg_stat_replication\u003c/code\u003e\u003c/dd\u003e\u003cdt\u003e字段\u003c/dt\u003e\u003cdd\u003e\u003ccode\u003ewrite_lag\u003c/code\u003e\u003c/dd\u003e\u003cdt\u003eSQL 类型\u003c/dt\u003e\u003cdd\u003e\u003ccode\u003einterval\u003c/code\u003e\u003c/dd\u003e\u003c/dl\u003e\u003ch3\u003e同版本中文手册定义\u003c/h3\u003e\u003cp\u003e从在本地将最近的 WAL 刷盘，到收到该备库已写入该 WAL（但尚未刷盘或应用）的通知之间经过的时间。如果该服务器被配置为同步备库，可用此值衡量在提交时 synchronous_commit 级别 remote_write 所导致的延迟。\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_replication"},{"label":"Field","value":"write_lag"},{"label":"SQL type","value":"interval"},{"label":"Units named in the field definition","value":"Not specified"},{"label":"Reset observation","value":"No stats_reset field is documented for this view"}],"facts_zh":[{"label":"视图","value":"pg_stat_replication"},{"label":"字段","value":"write_lag"},{"label":"SQL 类型","value":"interval"},{"label":"字段定义记载的单位","value":"未指定"},{"label":"重置条件","value":"手册未为此视图记载 stats_reset 字段"}],"field":"write_lag","manual_html":"","manual_path":"/docs/18/monitoring-stats.html","related":[{"label":"pg_stat_replication columns","url":"/wiki/catalog/pg_stat_replication/?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_replication view will contain one row per WAL sender process, showing statistics about replication to that sender's connected standby server. Only directly connected standbys are listed; no information is available about downstream standby servers."],"title":"View semantics"},{"paragraphs":["Read the same-version statistics collection and view documentation below for reset scope and visibility. 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This can be used to gauge the delay that synchronous_commit level remote_write incurred while committing if this server was configured as a synchronous standby."],"manual_html":"","related":[{"label":"pg_stat_replication columns","url":"/wiki/catalog/pg_stat_replication/?v=18"},{"label":"Statistics collection and reset functions","url":"/docs/18/monitoring-stats.html"}],"sections":[{"paragraphs":["The pg_stat_replication view will contain one row per WAL sender process, showing statistics about replication to that sender's connected standby server. Only directly connected standbys are listed; no information is available about downstream standby servers."],"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 write_lag FROM pg_catalog.pg_stat_replication;","paragraphs":["Example query; no execution result or measured value is asserted."],"title":"Inspect this field"}],"tables":[]}},"RequestedLocale":"en","Fallback":false,"Versions":["10","11","12","13","14","15","16","17","18","19","20"],"Locales":["en","zh-Hans"],"Signatures":null,"Spellings":null,"SQLState":null,"Evidence":null}