Hello All, I have noticed that a PostgreSQL 13 server went into recovery mode for 2 seconds during normal operation, not at startup, preventing users from connecting. Here is a log excerpt: 2023-03-29 10:45:46.973 CEST [114782] [unknown]@[unknown] LOG: connection received: host=10.150.52.16 port=53965 2023-03-29 10:45:47.088 CEST [114782] appuser@registryapp LOG: connection authorized: user=appuser database=registryapp 2023-03-29 10:48:57.483 CEST [115282] [unknown]@[unknown] LOG: connection received: host=192.168.1.22 port=63283 023-03-29 10:48:57.516 CEST [114942] LOG: database system was not properly shut down; automatic recovery in progress 2023-03-29 10:48:57.552 CEST [114942] LOG: redo starts at 25/CAB35218 2023-03-29 10:48:57.555 CEST [114942] LOG: invalid record length at 25/CAB75DC0: wanted 24, got 0 2023-03-29 10:48:57.555 CEST [114942] LOG: redo done at 25/CAB75D88 2023-03-29 10:48:57.575 CEST [115282] appuser@registryapp FATAL: the database system is in recovery mode 2023-03-29 10:48:57.590 CEST [115283] [unknown]@[unknown] LOG: connection received: host=10.150.1.1 port=63284 2023-03-29 10:48:57.875 CEST [114942] LOG: checkpoint starting: end-of-recovery immediate 2023-03-29 10:48:57.944 CEST [115287] appuser@registryapp FATAL: the database system is in recovery mode 2023-03-29 10:48:57.950 CEST [115288] [unknown]@[unknown] LOG: connection received: host=10.150.1.15 port=63288 2023-03-29 10:48:58.057 CEST [114942] LOG: checkpoint complete: wrote 32 buffers (0.0%); 0 WAL file(s) added, 0 removed, 0 recy cled; write=0.008 s, sync=0.075 s, total=0.202 s; sync files=11, longest=0.025 s, average=0.007 s; distance=258 kB, estimate=258 kB 2023-03-29 10:48:58.117 CEST [23615] LOG: database system is ready to accept connections The server definitely did not restart: postgres=# select pg_postmaster_start_time(); pg_postmaster_start_time --------------------------------------------- 2023-02-14 20:18:30.689732+01 I am wondering why the server would do crash recovery long after it has started. Is that normal? What would trigger such an event? Looking at the source code, my understanding is that recovery is implemented by the InitWalRecovery function, which is called only from the StartupXLOG function, whose comment says: "This must be called ONCE during postmaster or standalone-backend startup." I must be missing something. Regards, tamas
