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

Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> writes:
> Robert Haas wrote:
>> So, one of the problems in this patch as committed is that for any
>> process that doesn't show up in pg_stat_activity, there's no way to
>> see the wait event information. That sucks. I think there are
>> basically two ways to fix this:
>>
>> 1. Show all processes that have a PGPROC in pg_stat_activity,
>> including auxiliary processes and whatnot, and use some new field in
>> pg_stat_activity to indicate the process type.
>>
>> 2. Add a second view, say pg_stat_system_activity, to show the
>> processes that don't appear in pg_stat_activity. A bunch of columns
>> could likely be omitted, but there would be some duplication, too.
>>
>> Preferences?

> I vote 1.

If we go with #2, there would immediately be a need for a union view,
which would end up being exactly the same thing as the expanded display
proposed in #1. Seems like the hard way, so I agree with Alvaro.

regards, tom lane