Re: Linux: more cores = less concurrency.

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.

-Kevin