Re: Background Processes and reporting

On Sat, Mar 12, 2016 at 3:10 AM, Andres Freund <andres(at)anarazel(dot)de> wrote:
>
>
> > Similarly for the wait event stuff - checkpointer, wal writer,
> > background writer are in many cases processes that very often are
> > blocked on locks, IO and such. Thus restricting the facility to
> > database connected processes seems like a loss.
>
> I think one way to address this would be to not only report
> PgBackendStatus type processes in pg_stat_activity. While that'd
> obviously be a compatibility break, I think it'd be an improvement.
>

I think here another point which needs more thoughts is that many of the
pg_stat_activity fields are not relevant for background processes, ofcourse
one can say that we can keep those fields as NULL, but still I think that
indicates it is not the most suitable way to expose such information.

Another way could be to have new view like pg_stat_background_activity with
only relevant fields or try expose via individual views like
pg_stat_bgwriter.

Do you intend to get this done for 9.6 considering an add-on patch for wait
event information displayed in pg_stat_activity?

With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com