Re: PATCH: regular logging of checkpoint progress

On Thu, Sep 1, 2011 at 21:59, Tomas Vondra <tv(at)fuzzy(dot)cz> wrote:
> I've prepared a significantly simplified version of the patch. The two
> main changes are
>
> (a) it does not update the pg_stat_bgwriter anymore, it just prints an
> info to the server log
> (b) a new GUC is not required, it's driven by the log_checkpoints

The comment still refers to the checkpoint_update_limit.

> This version will log at least 10 'checkpoint status' lines (at 10%, 20%,
> 30%, ...) and whenever 5 seconds since the last log elapses. The time is
> not checked for each buffer but for 128 buffers.
>
> So if the checkpoint is very slow, you'll get a message every 5 seconds,
> if it's fast you'll get 10 messages.

I would personally find this very annoying. If I read it correctly,
anybody with a database with no problem at all but that has
log_checkpoints on suddenly got at least 10 times as many messages? I
generally try to advise my clients to *not* log excessively because
then they will end up not bothering to read the logs...

--
 Magnus Hagander
 Me: http://www.hagander.net/
 Work: http://www.redpill-linpro.com/