Re: Linux: more cores = less concurrency. - Mailing list pgsql-performance

On Mon, 11 Apr 2011 13:09:15 -0500, "Kevin Grittner"
<Kevin.Grittner@wicourts.gov> wrote:
> Glyn Astill <glynastill@yahoo.co.uk> wrote:
>
>> The new server uses 4 x 8 core Xeon X7550 CPUs at 2Ghz
>
> Which has hyperthreading.
>
>> our current servers are 2 x 4 core Xeon E5320 CPUs at 2Ghz.
>
> Which doesn't have hyperthreading.
>
> PostgreSQL often performs worse with hyperthreading than without.
> Have you turned HT off on your new machine?  If not, I would start
> there.

And then make sure you aren't running CFQ.

JD

>
> -Kevin

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