Re: Tracking wait event for latches

On Tue, Sep 27, 2016 at 8:39 PM, Thomas Munro
<thomas(dot)munro(at)enterprisedb(dot)com> wrote:
> Ok, if they really are independent then shouldn't we take advantage of
> that at call sites where we might be idle but we might also be waiting
> for the network?

I certainly didn't intend for them to be independent, and I don't
think they should be. I think it should be a hierarchy - as it is
currently. I think it's a bad idea to introduce the notational
overhead of having to pass through two integers rather than one
everywhere, and a worse idea to encourage people to think of the
wait_event_type and wait_event are related any way other than
hierarchically.

> Actually, I'm still not sold on "Activity" and "Client". I think
> "Idle" and "Network" would be better. Everybody knows intuitively
> what "Idle" means. "Network" is better than "Client" because it
> avoids confusion about user applications vs replication connections or
> clients vs servers.

Hmm, I could live with that, if other people like it.

> s/auxilliary/auxiliary/, but I wouldn't it be better to say something
> more general like "from another process in the cluster"? Background
> workers are not generally called auxiliary processes, and some of
> these wait points are waiting for those.

Agreed; or perhaps it could even be waiting for another regular backend.

--
Robert Haas
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