| Ranando King 2004-11-16, 2:13 pm |
| The main reason I didn't touch the IHT performance issues is because I'm
making what might be a terrible assumption: that the Niagara chip will be
using cores with truely "parallel thread" processing. IHT isn't quite that,
which is the reason it suffers such performance hits for software not
specifically designed to handle it. Also, the fact that you can enable HT on
SMP makes it somewhat ok to ignore those issues for this lopsided
comparison. Now... if we ignore the IHT features altogether as well as
Niagara's parallel threads, we basically end up comparing a single processor
to an 8 processor SMP system without the SMP bottlenecks. Under such
conditions, the statements I made still hold. There isn't that much work to
be done to support such a system. Current day applications will still
benefit greatly from the decreased process/cpu core ratio.
R. King
"Iceman" <1c3m4n@chi-mafia.org> wrote in message
news:1tit28p7sc7o7.dlg@icepick.org...
> On Mon, 15 Nov 2004 11:29:50 -0600, Ranando King wrote:
>
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>
> Interesting, but the Intel HT technology was not addressed by you. If HT
is
> enabled in the BIOS and you are running SMP you can expect a big
> performance hit. You have to enable HT with SMP in order to get some
> performance out of it and even that is weak at the current moment. The
> 2.6.x is currently addressing this situation to some extent.
>
> MS has already addressed this issue in XP, in fact did so soon after XP
was
> released, it took longer in W2K. Some software is already aware of it.
>
> Plus lets face it, for the typical user they are using Intel P4 and some
of
> the XEON HT CPU's as well.
|