Re: RFC: replace pg_stat_activity.waiting with something more descriptive

On Wed, Feb 24, 2016 at 7:14 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>
> On Mon, Feb 22, 2016 at 10:05 AM, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com>
wrote:
> >> I wouldn't bother tinkering with it at this point. The value isn't
> >> going to be recorded on disk anywhere, so it will be easy to change
> >> the way it's computed in the future if we ever need to do that.
> >>
> >
> > Okay. Find the rebased patch attached with this mail. I have moved
> > this patch to upcoming CF.
>
> I would call the functions pgstat_report_wait_start() and
> pgstat_report_wait_end() instead of pgstat_report_start_waiting() and
> pgstat_report_end_waiting().
>
> I think pgstat_get_wait_event_type should not return HWLock, a term
> that appears nowhere in our source tree at present. How about just
> "Lock"?
>
> I think the wait event types should be documented - and the wait
> events too, perhaps.
>

By above do you mean to say that we should document the name of each wait
event type and wait event. Documenting wait event names is okay, but we
have approximately 65~70 wait events (considering individuals LWLocks,
Tranches, Locks, etc), if we want to document all the events, then I think
we can have a separate table having columns (wait event name, description)
just below pg_stat_activity and have link to that table in wait_event row
of pg_stat_activity table. Does that matches your thought or you have
something else in mind?

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