Re: Performance degradation in commit ac1d794

On 2016-02-11 13:09:27 -0500, Robert Haas wrote:
> On Thu, Feb 11, 2016 at 12:53 PM, Andres Freund <andres(at)anarazel(dot)de> wrote:
> >> One problem is that it makes for misleading results if you try to
> >> benchmark 9.5 against 9.6.
> >
> > You need a really beefy box to show the problem. On a large/new 2 socket
> > machine the performance regression in in the 1-3% range for a pgbench of
> > SELECT 1. So it's not like it's immediately showing up for everyone.
> >
> > Putting it on the open items list sounds good to me.
>
> Well, OK, I've done that then. I don't really agree that it's not a
> problem; the OP said he saw a 3x regression, and some of my colleagues
> doing benchmarking are complaining about this commit, too. It doesn't
> seem like much of a stretch to think that it might be affecting other
> people as well.

Well, I can't do anything about that right now. I won't have the time to
whip up the new/more complex API we discussed upthread in the next few
days. So either we go with a simpler API (e.g. pretty much a cleaned up
version of my earlier patch), revert the postmaster deatch check, or
somebody else has to take lead in renovating, or we wait...

Andres