{"Entry":{"collection":"guc","key":"post_auth_delay","name":"post_auth_delay","aliases":[],"metadata":{"baseline":false,"boot_human":"Not specified","boot_val":null,"category":"Developer Options","category_zh":"","changed_in":["15"],"changes":[{"documentation_changed":false,"fields":{},"from":"8.1","status":"added","to":"8.2"},{"documentation_changed":true,"fields":{},"from":"8.4","status":"changed","to":"9.0"},{"documentation_changed":true,"fields":{},"from":"11","status":"changed","to":"12"},{"documentation_changed":false,"fields":{"short_desc":{"from":"Waits N seconds on connection startup after authentication.","to":"Sets the amount of time to wait after authentication on connection startup."}},"from":"14","status":"changed","to":"15"}],"content_hash":"7c43ebda11a0cb51ec0a6376ca4d9c968a59140237bd86958b84b0aa44c99ad9","context":"","default_changed_in":[],"default_history":[{"from":"9.0","to":"19","value":"0 s"}],"editorial":{"advice":{"olap":"Long analytical runs can amplify post_auth_delay's debug overhead and artifacts. Prefer standard EXPLAIN and statistics first, and isolate any developer experiment from normal users.","oltp":"Do not tune production OLTP with post_auth_delay. Enable it only for a bounded reproduction with an owner, log/disk budget, rollback condition, and evidence-capture plan; restore the default immediately afterward.","small":"Keep post_auth_delay at its upstream default. A small host has less spare CPU, disk, connection, and log capacity for developer instrumentation."},"mechanism":["post_auth_delay pauses a newly created backend after authentication succeeds, giving a developer time to attach a debugger to that process. Zero disables the delay.","The backend-context value is fixed at session start. Authentication has completed, so the session and server resources are already allocated while it sleeps.","This intentionally increases connection latency and can consume backend slots under connection storms. It is not a throttling, security, or connection-pooling control. Its backend context fixes the value during connection startup; an existing session cannot change it."],"pitfalls":["Leaving post_auth_delay enabled after the bounded diagnostic or recovery task.","Running the experiment on the only copy of production data.","Underestimating log, core-file, temporary-file, WAL, CPU, or connection-slot amplification.","Treating a server that merely starts or completes a query as proof that data and behavior are correct."],"references":[{"title":"PostgreSQL 19 Beta 4: post_auth_delay","url":"https://www.postgresql.org/docs/19/runtime-config-developer.html#GUC-POST-AUTH-DELAY"},{"title":"PostgreSQL 19 release notes","url":"https://www.postgresql.org/docs/19/release-19.html"}],"related":["pre_auth_delay","authentication_timeout","max_connections","log_connections"],"summary":"post_auth_delay — Sets the amount of time to wait after authentication on connection startup. Observed in PG9.0–19 Beta 4; its last measured boot default is 0 s in PG19 Beta 4, with backend context. This is a beta-snapshot fact and can change before PostgreSQL 19 GA."},"enumvals":[],"first_version":"8.2","group":"Developer Options","group_slug":"developer","imported_at":"2026-09-27T17:57:31.833634+08:00","intro_commit":{},"key":"post_auth_delay","last_version":"20","max_val":"","min_val":"","name":"post_auth_delay","position":313,"present_in":["8.2","8.3","8.4","9.0","9.1","9.2","9.3","9.4","9.5","9.6","10","11","12","13","14","15","16","17","18","19","20"],"short_desc":"The amount of time to delay when a new server process is started, after it conducts the authentication procedure.","short_desc_zh":"","source_rev":"english-manuals:609283e8f44f50ac974788408e1387a7d4f8a976003504fc3662149688861722","unit":"","vartype":"integer"}},"Definition":{"Collection":"guc","Key":"post_auth_delay","SourceDatabase":"center","Version":"18","SourceTable":"guc","SourceKey":"post_auth_delay","SourceRevision":"english-manuals:609283e8f44f50ac974788408e1387a7d4f8a976003504fc3662149688861722","Facts":{"boot_val":"0","category":"Developer Options","context":"backend","description":"The amount of time to delay when a new server process is started, after it conducts the authentication procedure. This is intended to give developers an opportunity to attach to the server process with a debugger. If this value is specified without units, it is taken as seconds. A value of zero (the default) disables the delay. This parameter cannot be changed after session start.","doc":{"anchor":"GUC-POST-AUTH-DELAY","file":"runtime-config-developer.html","lang":"en","sha256":"f5e7e39d176c642ac0799c87669ce2f6f60fcd97d109e290860ec74c36d7ecad","slug":"18"},"documented":true,"enumvals":null,"extra_desc":"This allows attaching a debugger to the process.","lang":"en","max_val":"2147","metadata_version":"18","min_val":"0","name":"post_auth_delay","short_desc":"Sets the amount of time to wait after authentication on connection startup.","source":"pg-settings-source-snapshot","unit":"s","vartype":"integer"},"ManualEvidence":{"doc":{"anchor":"GUC-POST-AUTH-DELAY","file":"runtime-config-developer.html","lang":"en","sha256":"f5e7e39d176c642ac0799c87669ce2f6f60fcd97d109e290860ec74c36d7ecad","slug":"18"}},"MeasuredEvidence":{"metadata_version":"18"}},"Text":{"Collection":"guc","Key":"post_auth_delay","SourceDatabase":"center","Version":"18","Locale":"en","Title":"post_auth_delay","Summary":"The amount of time to delay when a new server process is started, after it conducts the authentication procedure. This is intended to give developers an opportunity to attach to the server process with a debugger. If this value is specified without units, it is taken as seconds. A value of zero (the default) disables the delay. This parameter cannot be changed after session start.","BodyHTML":"\u003cp\u003eThe amount of time to delay when a new server process is started, after it conducts the authentication procedure. This is intended to give developers an opportunity to attach to the server process with a debugger. If this value is specified without units, it is taken as seconds. A value of zero (the default) disables the delay. This parameter cannot be changed after session start.\u003c/p\u003e","SourceRevision":"english-manuals:609283e8f44f50ac974788408e1387a7d4f8a976003504fc3662149688861722","ContentHash":"bbc526f863a902c6e9830cb0730b89f6f8d028201aa9eb7e9759db4849adbdff","Payload":{"description":"The amount of time to delay when a new server process is started, after it conducts the authentication procedure. This is intended to give developers an opportunity to attach to the server process with a debugger. If this value is specified without units, it is taken as seconds. A value of zero (the default) disables the delay. This parameter cannot be changed after session start."}},"RequestedLocale":"zh-Hans","Fallback":true,"Versions":["10","11","12","13","14","15","16","17","18","19","20","8.2","8.3","8.4","9.0","9.1","9.2","9.3","9.4","9.5","9.6"],"Locales":["en"],"Signatures":null,"Spellings":null,"SQLState":null,"Evidence":null}