{"Entry":{"collection":"waitevent","key":"client/WalSenderWriteData","name":"WalSenderWriteData","aliases":["WalSenderWriteData"],"metadata":{"aliases":["WalSenderWriteData"],"changed_in":[],"changes":[{"from":"9.6","moved":null,"renamed":null,"reworded":null,"status":"added","to":"10"}],"content_hash":"8284f80a84aa2006689dc6bb4e031971b9db589f89f6e972f20c89c0b0ff05b1","dossier":{"actions":{"en":["Check state and transaction age before counting the wait as load.","Correlate with the owning application, pool, and network path.","Fix consumer backpressure or pool policy rather than repeatedly terminating connections."],"zh":["先看 state 与事务年龄，再决定它是否算负载。","关联负责的应用、连接池与网络路径。","修复消费者背压或连接池策略，不要反复终止连接。"]},"diagnostic_sql":[{"id":"sessions","min_version":"13","sql":"SELECT pid, backend_type, usename, datname, application_name,\n       state, now() - query_start AS query_age,\n       now() - xact_start AS xact_age,\n       wait_event_type, wait_event,\n       pg_blocking_pids(pid) AS blocking_pids,\n       left(query, 160) AS query\nFROM pg_stat_activity\nWHERE wait_event_type = 'Client'\n  AND wait_event = 'WalSenderWriteData'\nORDER BY query_age DESC NULLS LAST;","title":"Sessions waiting on Client/WalSenderWriteData","title_zh":"正在等待 Client/WalSenderWriteData 的会话"},{"id":"cohort","min_version":"13","sql":"SELECT wait_event, count(*) AS waiting_sessions,\n       count(*) FILTER (WHERE state = 'active') AS active_waiters,\n       max(now() - query_start) AS oldest_query\nFROM pg_stat_activity\nWHERE wait_event_type = 'Client'\nGROUP BY wait_event\nORDER BY waiting_sessions DESC, wait_event;","title":"Current Client cohort","title_zh":"当前 Client 等待分布"},{"id":"lock_objects","min_version":"13","sql":"SELECT a.pid, l.locktype, l.mode, l.granted, l.fastpath,\n       d.datname, n.nspname, c.relname,\n       l.page, l.tuple, l.virtualxid, l.transactionid,\n       l.classid, l.objid, l.objsubid\nFROM pg_stat_activity AS a\nLEFT JOIN pg_locks AS l ON l.pid = a.pid\nLEFT JOIN pg_database AS d ON d.oid = l.database\nLEFT JOIN pg_class AS c\n  ON c.oid = l.relation\n AND l.database = (\n       SELECT oid FROM pg_database WHERE datname = current_database()\n     )\nLEFT JOIN pg_namespace AS n ON n.oid = c.relnamespace\nWHERE a.wait_event_type = 'Client'\n  AND a.wait_event = 'WalSenderWriteData'\nORDER BY a.pid, l.granted, l.locktype, l.mode;","title":"Lock and relation context for these sessions","title_zh":"这些会话的锁与关系上下文"}],"emission":{"status":"active","verified_release":"18.6"},"gucs":["wal_buffers","synchronous_commit","max_connections","idle_in_transaction_session_timeout"],"incident_pattern":{"en":"","zh":""},"mechanism":{"en":"`WAIT_EVENT_WAL_SENDER_WRITE_DATA` at `src/backend/replication/walsender.c:1653` is the grep-verified reporting path. The public identity/resource is mapped at `src/backend/utils/activity/wait_event_names.txt:93`. The instrumented operation is: Waiting for any activity when processing replies from WAL receiver in WAL sender process. The frontend protocol path reports WalSenderWriteData immediately before a socket, TLS/GSS, or replication-client operation blocks. PostgreSQL is waiting for the remote side or network to progress.","zh":"`WAIT_EVENT_WAL_SENDER_WRITE_DATA` 位于 `src/backend/replication/walsender.c:1653`，是经 grep 核验的报告路径。公共身份/资源映射位于 `src/backend/utils/activity/wait_event_names.txt:93`。探针覆盖的操作是：在 WAL sender 进程中处理 WAL receiver 的回复时，等待发生任何活动。前端协议路径在套接字、TLS/GSS 或复制客户端操作即将阻塞前报告 WalSenderWriteData；PostgreSQL 正在等待远端或网络推进。"},"metrics":["waiting_sessions","wait_event_share","wal_bytes","wal_write_time","active_backends"],"normal":{"en":"Idle ClientRead sessions are normal connection-pool inventory.","zh":"空闲状态的 ClientRead 通常只是连接池存量。"},"official_descriptions":{"13":"Waiting for any activity when processing replies from WAL receiver in WAL sender process.","14":"Waiting for any activity when processing replies from WAL receiver in WAL sender process.","15":"Waiting for any activity when processing replies from WAL receiver in WAL sender process.","16":"Waiting for any activity when processing replies from WAL receiver in WAL sender process.","17":"Waiting for any activity when processing replies from WAL receiver in WAL sender process","18":"Waiting for any activity when processing replies from WAL receiver in WAL sender process"},"record_kind":"event","source_locations":[{"commit":"724edf9bde9d356724ad384a2e196edc3c9f80f7","excerpt":"WAIT_EVENT_WAL_SENDER_WRITE_DATA);","grep_pattern":"WAIT_EVENT_WAL_SENDER_WRITE_DATA","grep_verified":true,"kind":"trigger","line":1653,"major":18,"path":"src/backend/replication/walsender.c","status":"live_trigger","symbol":"WAIT_EVENT_WAL_SENDER_WRITE_DATA","tag":"REL_18_6","url":"https://github.com/postgres/postgres/blob/REL_18_6/src/backend/replication/walsender.c#L1653","version":"18.6"},{"commit":"724edf9bde9d356724ad384a2e196edc3c9f80f7","excerpt":"WAL_SENDER_WRITE_DATA\t\"Waiting for any activity when processing replies from WAL receiver in WAL sender process.\"","grep_pattern":"WAL_SENDER_WRITE_DATA","grep_verified":true,"kind":"catalog_definition","line":93,"major":18,"path":"src/backend/utils/activity/wait_event_names.txt","status":"live_trigger","symbol":"WAL_SENDER_WRITE_DATA","tag":"REL_18_6","url":"https://github.com/postgres/postgres/blob/REL_18_6/src/backend/utils/activity/wait_event_names.txt#L93","version":"18.6"}],"source_status":"live_trigger","trouble":{"en":"Investigate active writes, handshakes, old idle-in-transaction sessions, connection exhaustion, or replication-client stalls.","zh":"活动写入、握手、很老的 idle in transaction、连接耗尽或复制客户端停滞时需要调查。"}},"first_version":"10","has_dossier":true,"imported_at":"2026-09-27T17:57:32.531417+08:00","key":"client/walsenderwritedata","last_version":"20","name":"WalSenderWriteData","position":33,"present_in":["10","11","12","13","14","15","16","17","18","19","20"],"slug":"wal-sender-write-data","source_rev":"english-manuals:31011152851d741b520f0ae0c4eb46aac48e20367cd78885172780e303ee8b42","summary":"Waiting for any activity when processing replies from WAL receiver in WAL sender process.","summary_zh":"","type":"Client","type_slug":"client","type_variants":["Client"]}},"Definition":{"Collection":"waitevent","Key":"client/WalSenderWriteData","SourceDatabase":"center","Version":"18","SourceTable":"waitevent","SourceKey":"client/walsenderwritedata","SourceRevision":"english-manuals:31011152851d741b520f0ae0c4eb46aac48e20367cd78885172780e303ee8b42","Facts":{"description":"Waiting for any activity when processing replies from WAL receiver in WAL sender process.","description_zh":"","doc":{"anchor":"WAIT-EVENT-CLIENT-TABLE","file":"monitoring-stats.html","lang":"en","sha256":"aa979eed08627fbf715a9d792094a162a73671db5af810f3ab2aad3e073d5722","slug":"18"},"lang":"en","name":"WalSenderWriteData","source":"english-manual","type":"Client","zh_from":""},"ManualEvidence":{"doc":{"anchor":"WAIT-EVENT-CLIENT-TABLE","file":"monitoring-stats.html","lang":"en","sha256":"aa979eed08627fbf715a9d792094a162a73671db5af810f3ab2aad3e073d5722","slug":"18"}},"MeasuredEvidence":{}},"Text":{"Collection":"waitevent","Key":"client/WalSenderWriteData","SourceDatabase":"pgweb","Version":"18","Locale":"zh-Hans","Title":"WalSenderWriteData","Summary":"在 WAL 发送进程中处理 WAL 接收进程的回复时，等待任何活动。","BodyHTML":"\u003cp\u003e在 WAL 发送进程中处理 WAL 接收进程的回复时，等待任何活动。\u003c/p\u003e","SourceRevision":"2026-08-31@34d13c8","ContentHash":"be6d4a8c1e8dfe884e8e6dcd0ceaeb3e1b6f38760eb11d5269f1d9eeb5c82972","Payload":{"description_zh":"在 WAL 发送进程中处理 WAL 接收进程的回复时，等待任何活动。","zh_from":"doc"}},"RequestedLocale":"zh-Hans","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}