Re: postgres 9.3 vs. 9.4

On 09/18/2014 08:09 AM, Mkrtchyan, Tigran wrote:
>>> 9.4beta2:
>>> > >
>> > ...
>> >
>>> > >         0.957854        END;
>>> > >
>> >
>> > Looks like IO.
> Postgres internal IO? May be. We get 600MB/s on this SSDs.

While it's possible that this is a Postgres issue, my first thought is
that the two SSDs are not actually identical.  The 9.4 one may either
have a fault, or may be mostly full and heavily fragmented.  Or the Dell
PCIe card may have an issue.

You are using "scale 1" which is a < 1MB database, and one client and 1
thread, which is an interesting test I wouldn't necessarily have done
myself.  I'll throw the same test on one of my machines and see how it does.

--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com