Re: exposing wait events for non-backends (was: Tracking wait event for latches)

On Thu, Mar 9, 2017 at 2:30 PM, Peter Eisentraut
<peter(dot)eisentraut(at)2ndquadrant(dot)com> wrote:
> Perhaps I'm confused by the title of this thread/CF entry, but
> background workers already do show up in pg_stat_activity. (You can
> verify that by testing the background sessions patch.) So which
> additional things are we aiming to see with this?

All the processes that don't normally show up in pg_stat_activity,
such as auxiliary processes.

> In practice, I think it's common to do a quick select * from
> pg_stat_activity to determine whether a database instance is in use.
> (You always see your own session, but that's easy to eyeball.) If we
> add all the various background processes by default, that will make
> things harder, especially if there is no straightforward way to filter
> them out.
>
> Perhaps a pg_stat_user_* and pg_stat_system_* split like we have for
> some of the statistics tables would be useful?

I thought of the same kind of thing, and it was discussed upthread.
There seemed to be more votes for keeping it all in one view, but that
could change if more people vote.

--
Robert Haas
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