Re: is xeon hyperthreading considered good or bad?

tony broughton <tonybDELETE_THIS_SPAM_BLOCKER17v@xxxxxxxxxxx> wrote:
I'm running 6.2 release on a dual 2.4GHz P4 Xeon machine
(Prestonias) with hyperthreading on in bios. I recompiled the kernel
with SMP on, and have specified machdep.hyperthreading_allowed=1
in /etc/sysctl.conf.

Top now shows me 4 cpus with processes running on all four
cpu ids.

Is this considered a good way to run my hardware? I've noticed
some appends on mailing lists about hyper-threading being
sub-optimal with the fbsd scheduler (I'm using 4BSD) and
wondered whether I'd get better performance with HTT disabled?

The machine is used as a development workhorse with lots
of software compilation.

On my P4 (single core) hypertreading has rather positive benefits. Of
course not to the point of a real dual core.


Thanks for any opinions - Tony

--

Michel TALON

.

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