Re: Intel Xeon dual-core HTT

Tech Tip: Click here to run a free scan for Windows Errors and optimize PC performance



"AnthonyThomas" <AnthonyThomas@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:B3C39944-23CB-4C0B-9DBB-40EB01868E0D@xxxxxxxxxxxxxxxx
That makes sense in order to distinguish between HTT and processors, but
are
there CPU instructions that distinguish between core and socket?


I don't know. It may be that each core reports as a "logical" processor and
when HT is turned on, each core reports as two logical processors.

It also makes sense as far as the logical cap as a limitation of memory
map,
but that would be true of Datacenter Edition too, except that edition
would
allow all of them to be physical processors.

In that case there is no difference between a logical and a physical
processor from the OS perspective.


Thanks.


Anthony Thomas

"Michael D. Ober" wrote:


There are new CPU level instructions to query the number of logical
processors per CPU. Windows XP and 2003 are aware of these instructions
and
MS has coded these OSs to limit based on physical processors. This
said,
there is still a hard limit of 32 logical processors for 32-bit versions
of
Windows and 64 logical processors for 64-bit versions of windows. This
is
because the processor affinity instructions use a simple bitmap of a
machine
word to allocate processor usage to an application.

Mike Ober.

"AnthonyThomas" <AnthonyThomas@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in
message
news:0D44DB09-C990-4D4A-9033-8A46B6CE5C80@xxxxxxxxxxxxxxxx
Thanks for the reply, but I understand the difference between logicl
and
physical processors, but since Windows does not necessarily make this
distinction, how is the 8 processor limit controlled when you have
more
than
8 logical processors?

The new dual-core Xeon's with HTT turned on, are 4 logical processors
per
socket. So, what happens when I have a 4-way of these processors
installed?
That would make 16 logical processors, but Win2K3 EE is only supposed
to
work
on up to 8.

The question is will it recognize all 16 and use them all, or only up
to
8?

I don't care what the OS sees, but the MAXIMUM it will see when you
use
these hybrid type processors.


Anthony Thomas


"Admiral Q" wrote:

Well I can say I'm running Win2k3 R2 x64 on a box with 2x2.8Ghz Dual
Core
Processors with HT - with HT off, Win2k3 sees 4 processors, with HT
on,
it
sees 8 and uses them as such.

--

Star Fleet Admiral Q @ your service!
Google is your friend!
http://www.google.com


"AnthonyThomas" <AnthonyThomas@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in
message
news:6F6B5E6F-5492-4D04-8617-E87A5891B6A4@xxxxxxxxxxxxxxxx
Anyone know how Win2K3 EE supports the new Intel Xeon dual-core
HTT
processors?

If I install 8 of these bad boys, will the OS see a maximum of 8
logical
processors or the 32 that the subsystem is presenting?

What about the HP tests of the new Itanium 2 Montecito chips that
are
also
supposed to be dual-core, HTT?

Anyone have any redirects to some documentation of the bahavior?

Thanks.

Sincerely,


Anthony Thomas













.