Re: Dual Xeon + HW RAID question

But CPU affinity isn't realated to hyperthreading, as far as I know.
CPU affinity tries to keep processes on the same cpu in case there is
still valuable info in the cpu cache.

---------------------------------------------------------------------------

Jord Tanner wrote:
> The Linux 2.6 kernel will have the ability to set CPU affinity for
> specific processes. There is a patch for the 2.4 kernel at
> http://www.kernel.org/pub/linux/kernel/people/rml/cpu-affinity
>
> RedHat 9 already has support for CPU affinity build in.
>
> The July 2003 issue of Linux Journal includes a little C program (on
> page 20) that gives you a shell level interface to the CPU affinity
> system calls, so you can dynamically assign processes to specific CPUs.
> I haven't tried it, but it looks very cool (my only SMP machine is in
> production, and I don't want to mess with it). If you try it out, please
> share your experiences with the list.
>
>
> Jord Tanner
> Independent Gecko Consultants
>
> On Tue, 2003-07-22 at 10:10, SZUCS G?bor wrote:
> > "by default" -- do you mean there is a way to tell Linux to favor the second
> > real cpu over the HT one? how?
> >
> > G.
> > ------------------------------- cut here -------------------------------
> > ----- Original Message -----
> > From: "Bruce Momjian" <pgman(at)candle(dot)pha(dot)pa(dot)us>
> > Sent: Tuesday, July 22, 2003 6:26 PM
> > Subject: Re: [PERFORM] Dual Xeon + HW RAID question
> >
> >
> > > Right, I simplified it. The big deal is whether the OS favors the
> > > second real CPU over one of the virtual CPU's on the same die --- by
> > > default, it doesn't. Ever if it did work perfectly, you are talking
> > > about going from 1 to 1.4 or 2 to 2.8, which doesn't seem like much.
> >
> >
> > ---------------------------(end of broadcast)---------------------------
> > TIP 8: explain analyze is your friend
> --
> Jord Tanner <jord(at)indygecko(dot)com>
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 3: if posting/reading through Usenet, please send an appropriate
> subscribe-nomail command to majordomo(at)postgresql(dot)org so that your
> message can get through to the mailing list cleanly
>

--
Bruce Momjian | http://candle.pha.pa.us
pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073