Re: Shutdown indefinitely stuck due to unflushed FPI_FOR_HINT record

Fujii Masao <masao.fujii@gmail.com>

From: Fujii Masao <masao.fujii@gmail.com>
To: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com>
Cc: Alexander Lakhin <exclusion@gmail.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2026-03-06T07:48:06Z
Lists: pgsql-hackers
On Fri, Mar 6, 2026 at 8:46 AM Fujii Masao <masao.fujii@gmail.com> wrote:
>
> On Thu, Mar 5, 2026 at 5:40 PM Anthonin Bonnefoy
> <anthonin.bonnefoy@datadoghq.com> wrote:
> > So it was relying on GetInsertRecPtr() instead of
> > GetXLogInsertRecPtr(). As mentioned in the thread, GetInsertRecPtr()
> > only returns the position of the last full xlog page, meaning it
> > doesn't fix the issue we have where the last partial page contains a
> > continuation record.
> >
> > Testing the XLogFlush(GetInsertRecPtr()) patch with my script, I still
> > get the shutdown stuck issue.
> >
> > Using GetXLogInsertRecPtr() is required to make sure the last partial
> > page is correctly flushed.
>
> Since GetXLogInsertRecPtr() returns a bogus LSN and XLogFlush() does
> almost nothing during recovery, I added a !RecoveryInProgress() check
> as follows. I've attached the latest version of the patch and updated
> the commit message.
>
> - if (got_STOPPING)
> - XLogBackgroundFlush();
> + if (got_STOPPING && !RecoveryInProgress())
> + XLogFlush(GetXLogInsertRecPtr());

I've pushed the patch. Thanks!

Regards,

-- 
Fujii Masao



Commits

  1. Fix WAL flush LSN used by logical walsender during shutdown

  2. Use GetXLogInsertEndRecPtr in gistGetFakeLSN

  3. Fix publisher shutdown hang caused by logical walsender busy loop.