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From: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Date: Fri, 28 Jan 2022 12:24:48 +0530
Message-ID: <CALj2ACUGWAC56yqhVOisNPXhewfRdeHG4NGTOK_sOStL=7yP+w@mail.gmail.com>
Subject: Report checkpoint progress with pg_stat_progress_checkpoint (was:
 Report checkpoint progress in server logs)
To: Nitin Jadhav <nitinjadhavpostgres@gmail.com>
Cc: Bruce Momjian <bruce@momjian.us>, Tom Lane <tgl@sss.pgh.pa.us>, 
	Magnus Hagander <magnus@hagander.net>, 
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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On Fri, Jan 21, 2022 at 11:07 AM Nitin Jadhav
<nitinjadhavpostgres@gmail.com> wrote:
>
> > I think the right choice to solve the *general* problem is the
> > mentioned pg_stat_progress_checkpoints.
> >
> > We may want to *additionally* have the ability to log the progress
> > specifically for the special cases when we're not able to use that
> > view. And in those case, we can perhaps just use the existing
> > log_startup_progress_interval parameter for this as well -- at least
> > for the startup checkpoint.
>
> +1
>
> > We need at least a trace of the number of buffers to sync (num_to_scan) before the checkpoint start, instead of just emitting the stats at the end.
> >
> > Bharat, it would be good to show the buffers synced counter and the total buffers to sync, checkpointer pid, substep it is running, whether it is on target for completion, checkpoint_Reason
> > (manual/times/forced). BufferSync has several variables tracking the sync progress locally, and we may need some refactoring here.
>
> I agree to provide above mentioned information as part of showing the
> progress of current checkpoint operation. I am currently looking into
> the code to know if any other information can be added.

As suggested in the other thread by Julien, I'm changing the subject
of this thread to reflect the discussion.

Regards,
Bharath Rupireddy.