On Wed, 2007-01-10 at 14:15, Jim C. Nasby wrote:
> On Wed, Jan 03, 2007 at 12:24:24PM -0500, Jeremy Haile wrote:
> > I am sure that this has been discussed before, but I can't seem to find
> > any recent posts. (I am running PostgreSQL 8.2)
> >
> > I have always ran PostgreSQL on Linux in the past, but the company I am
> > currently working for uses Windows on all of their servers. I don't
> > have the luxury right now of running my own benchmarks on the two OSes,
> > but wanted to know if anyone else has done a performance comparison. Is
> > there any significant differences?
>
> One thing to consider... I've seen a case or two where pgbench running
> on windows with HyperThreading enabled was actually faster than with it
> turned off. (General experience has been that HT hurts PostgreSQL). I
> suspect that the windows kernel may have features that allow it to
> better utilize HT than linux.
I've also seen a few comments in perform (and elsewhere) in the past
that newer linux kernels seem to handle HT better than older ones, and
also might give better numbers for certain situations.
Note that you should really test with a wide variety of loads (i.e. a
lot of parallel loads, a few etc...) to see what the curve looks like.
If HT gets you 10% gain on 4 or fewer clients, but 20% slower with 8
clients, then hyperthreading might be a not so good choice.