Re: Re: [COMMITTERS] pgsql: Avoid extra locks in GetSnapshotData if old_snapshot_threshold <

On Wed, Apr 13, 2016 at 3:01 PM, Andres Freund <andres(at)anarazel(dot)de> wrote:

> If you want me to rn some other tests I can, but ISTM we have the
> data we need?

Thanks for the additional detail on how this was run. I think I
still need a little more context, though:

What is the kernel on which these tests were run?

Which pg commit were these tests run against?

If 2201d801 was not included in your -1 tests, have you identified
where the 2% extra run time is going on -1 versus reverted? Since
several other threads lately have reported bigger variation than
that based on random memory alignment issues, can we confirm that
this is a real difference in what is at master's HEAD? Of course,
I'm still scheduled to test on bare metal machines in a couple
days, on two different architectures, so we'll have a few more data
points after that.

--
Kevin Grittner
EDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company