Re: Dual core Opterons beating quad core Xeons?

On Dec 19, 2007 12:59 PM, Joshua D. Drake <jd(at)commandprompt(dot)com> wrote:
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> On Wed, 19 Dec 2007 13:50:29 -0500 (EST)
> Greg Smith <gsmith(at)gregsmith(dot)com> wrote:
>
> > > With PG 8.2 and 8.3, is it still pretty much limited to 8 cores
> > > making 2 of the quad core Xeons redundant or detrimental?
> >
> > Where'd you get the idea 8 cores was a limit? As cores go up
> > eventually you run out of disk or memory bandwidth, but how that
> > plays out is very application dependant and there's no hard line
> > anywhere.
>
> Actually this is not true. Although I have yet to test 8.3. It is
> pretty much common knowledge that after 8 cores the acceleration of
> performance drops with PostgreSQL...

I thought Tom had played with some simple hacks that got the scaling
pretty close to linear for up to 16 cores earlier this year...