HI This patch looks good to me. The issue is clear: unlike other fixed-size stats kinds (archiver, bgwriter, checkpointer), the injection_points stats can be updated concurrently by multiple backends. Without synchronization, this can lead to inconsistent changecount state and assertion failures in pgstat_begin_changecount_write(), as shown in your reproduction.
Thanks On Mon, Sep 29, 2025 at 3:29 PM Chao Li <[email protected]> wrote: > > > On Sep 29, 2025, at 14:27, Michael Paquier <[email protected]> wrote: > > On Mon, Sep 29, 2025 at 09:46:05AM +0800, Chao Li wrote: > > I saw pg_state_begin_changecount_write() is called multiple places, > as you mention, for example bgwriter. > > > I've mentioned that in my first email, and put in details: > - pgstat_report_bgwriter() is called once, by the bgwriter. > - pgstat_report_checkpointer() is called three time, all by the > checkpointer. > - pgstat_report_archiver() is called twice, all by pgarch.c. > > So all of them don't have a problem, two calls cannot happen > concurrently. > -- > Michael > > > Thanks for the clarification. Then the patch looks good to me. > > Best regards, > -- > Chao Li (Evan) > HighGo Software Co., Ltd. > https://www.highgo.com/ > > > > >
