Thread

  1. Re: BUG #19490: Streaming standby on 16.14 stops applying WAL on MultiXactOffsetSLRU when primary is 16.8

    Andrey Borodin <x4mmm@yandex-team.ru> — 2026-05-21T07:07:31Z

    Thanks for the report!
    
    Oh, this seems to be from the "gift that keeps on giving" department.
    Related to [0]
    
    > On 20 May 2026, at 14:16, PG Bug reporting form <noreply@postgresql.org> wrote:
    > 
    > Downgrading the standby binary to 16.12 (16.12-1.pgdg22.04+1) against
    > the same data directory restored normal replay. After 60s under the same
    > workload pg_stat_slru shows only 2 hits / 0 reads on MultiXact.
    
    Are you sure that it's not 16.11 that is resolving the problem?
    Can you get a backtrace of hanging startup process with debug symbols? Or obtain last
    replayed LSN and do a WAL dump in the area of deadlocked startup.
    
    I don't see how this might be a result of [1] and [2], so, perhaps, it's some more peculiarities
    from [3]. But 16.12 has [3]...
    
    
    Best regards, Andrey Borodin.
    
    
    [0] https://www.postgresql.org/message-id/flat/CACV2tSw3VYS7d27ftO_cs%2BaF3M54%2BJwWBbqSGLcKoG9cvyb6EA%40mail.gmail.com
    [1] https://git.postgresql.org/cgit/postgresql.git/commit/?h=REL_16_STABLE&id=77dff5d937b192b85c55bce822e7413ff7dda6eb
    [2] https://git.postgresql.org/cgit/postgresql.git/commit/?h=REL_16_STABLE&id=23064542f8bdcbc4b6a513cac8ceed67c0d2336e
    [3] https://git.postgresql.org/cgit/postgresql.git/commit/?h=REL_16_STABLE&id=6351669130782ed01eed3aeefded171789d0bc35