From: Marc Dietrich <Marc.Dietrich@hrz.uni-giessen.de>
To: Hugh Dickins <hugh@veritas.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Hyperthreading
Date: Thu, 22 Aug 2002 16:36:54 +0200 [thread overview]
Message-ID: <200208221636.54108.marc.dietrich@physik.uni-giessen.de> (raw)
In-Reply-To: <Pine.LNX.4.44.0208221455490.1253-100000@localhost.localdomain>
Am Donnerstag, 22. August 2002 :06 schrieben Sie:
> On Thu, 22 Aug 2002, Marc Dietrich wrote:
> > On Wed, 21 Aug 2002, Hugh Dickins wrote:
> > > You do need CONFIG_SMP and a processor capable of HyperThreading,
> > > i.e. Pentium 4 XEON; but CONFIG_MPENTIUM4 is not necessary for HT,
> > > just appropriate to that processor in other ways.
> >
> > I used KNOPPIX on a 2 way Dell WS 530 (Xeon 2.0 GHz). This distribution
> > has CONFIG_M386 set (as most others also?) and HT was not enabled. I
> > compiled the kernel myself (same config as KNOPPIX but with
> > CONFIG_MPENTIUM4) and HT gets enabled. So is _does_ matter for which
> > processor the kernel is optimized.
>
> I'm surprised - perhaps the Knoppix distribution did not have SMP enabled
> itself, but installed a config with CONFIG_SMP? Or you built more recent
> kernel sources (2.4.19 defaults to HT on) than the Knoppix distribution
> (vanilla 2.4.18 defaults to HT off)?
I don't think so. Original kernel gives me 2 penguins and cpuinfo shows 2
cpu's. Kernel is 2.4.19 with xfs patches and there is no "noht" option. I
attached a dmesg file of this one. Btw, setting the processor also sets some
other options (CMPXCHG, TCS, PGE, ...).
> It would be awkward for me to try CONFIG_M386 on our P4 Xeon, but I did
> just try building a CONFIG_M586 CONFIG_SMP kernel for it, which behaved
> as I expected: /proc/cpuinfo showed 4 cpus, but only 2 cpus when booted
> with "noht".
Give it a try. A dual Xeon won't take to much time to compile a new kernel ;)
Greetings
Marc
--
Marc Dietrich
next prev parent reply other threads:[~2002-08-22 14:33 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-08-22 9:15 Hyperthreading Marc Dietrich
2002-08-22 14:06 ` Hyperthreading Hugh Dickins
2002-08-22 14:36 ` Marc Dietrich [this message]
-- strict thread matches above, loose matches on Subject: below --
2003-11-25 9:44 hyperthreading Gábor Lénárt
2003-11-25 9:48 ` hyperthreading Emiliano 'AlberT' Gabrielli
2003-11-25 10:05 ` hyperthreading Gábor Lénárt
2003-11-25 10:16 ` hyperthreading Arjan van de Ven
2003-11-25 10:32 ` hyperthreading Måns Rullgård
2003-11-25 10:45 ` hyperthreading Mikael Pettersson
2003-11-29 13:29 ` hyperthreading Bill Davidsen
2003-12-01 10:53 ` hyperthreading Emiliano 'AlberT' Gabrielli
2003-11-25 10:22 ` hyperthreading Karl Pitrich
2002-08-22 12:58 Hyperthreading Nir Soffer
2002-08-22 14:30 ` Hyperthreading Hugh Dickins
2002-08-21 22:56 Hyperthreading Nakajima, Jun
2002-08-21 23:45 ` Hyperthreading Alan Cox
2002-08-21 11:32 Hyperthreading Reed, Timothy A
2002-08-21 13:48 ` Hyperthreading James Bourne
2002-08-21 17:33 ` Hyperthreading Hugh Dickins
2002-08-21 19:34 ` Hyperthreading James Bourne
2002-08-21 21:16 ` Hyperthreading Kelsey Hudson
2002-08-21 21:55 ` Hyperthreading Banai Zoltan
2002-08-22 8:05 ` Hyperthreading venom
2002-08-26 19:00 ` Hyperthreading Kelsey Hudson
2002-08-22 8:00 ` Hyperthreading venom
2002-08-23 7:28 ` Hyperthreading Gilad Ben-Yossef
2002-08-23 8:10 ` Hyperthreading Hugh Dickins
2002-08-23 8:27 ` Hyperthreading Alan Cox
2002-08-23 8:12 ` Hyperthreading venom
2002-04-18 1:52 Hyperthreading Holzrichter, Bruce
2002-04-17 20:34 Hyperthreading Holzrichter, Bruce
2002-04-17 22:48 ` Hyperthreading Martin J. Bligh
2002-04-18 1:21 ` Hyperthreading James Bourne
2002-04-17 20:02 SMP P4 APIC/interrupt balancing James Bourne
2002-04-17 21:10 ` Hyperthreading Martin J. Bligh
2002-04-17 20:15 ` Hyperthreading Robert Love
2002-04-17 20:23 ` Hyperthreading Dave Jones
2002-04-17 21:24 ` Hyperthreading Jeff V. Merkey
2002-04-17 20:25 ` Hyperthreading James Bourne
2002-04-17 21:26 ` Hyperthreading Jeff V. Merkey
2002-04-18 0:31 ` Hyperthreading Martin J. Bligh
2002-04-18 4:50 ` Hyperthreading Jeff V. Merkey
2002-04-17 22:12 ` Hyperthreading Alan Cox
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