XPe & HyperThreading & EWF

[Nikolai Vorontsov]

Hi, All!

I'm trying to make a bootable CD for the dual XEON machine (TYAN Tiger
i7500 motherboard to be precize). I did a lot CDs for the P3, P4 - so I
do know how to make it ) But not in this particular case.

So, I have a 'normal' XPe image (XPeSP1) that works on this machine
(with all devices recognized and 2(4) CPUs shown in the TaskManager) -
means that my PMQ is OK and all devices are in database.

I have reduced target version for the ElTorito disk. It works for the P4
and P3 machines (with the different devices set of course).

When I'm trying to boot the reduced ElTorito version (with all drivers
for the XEON machine) I'm getting problem even before etprep /all command.

The EWF partition is been created and image starts from the hdd *only*
if I *switched off HyperThreading* and left 1 CPU. In this case all
works. I mean ewgmgr shows partition, my apps running - OK.
When I switch on HyperThreading - I get BSOD 0x000000C2 (0x00000007,
0x00000CD4, 0x0, 0xF8990C4C). I switch HT off - all works.

So, as I see the problem arises when I have more than 1 CPU and EWF.

Has anybody succeeded with building ElTorito CD that works on a
multiprocessor PC?
Did MS test EWF on the ACPI Multiprocessor PC?

Thanks in advance, Nick.

 

[Nikolai Vorontsov]

Hi, All!

In addition to my prevous post:

After ETPREP /all, making an iso and burning a CD - I got the 0x0000007B
error :-( even with 1 CPU. I tested with the exact drivers, with
Standard Dual Channel IDE controller - no way.
I have an impression that something is wrong in the EWF...

BTW, etprep has reported that it can't swap drives (0x01), but as
somebody from MS said - it's not a problem.

Hi, Jon and other guys from MS - could you confirm that ElTorito disk
can boot on a dual CPU machine with Intel E7500 chipset?

Thanks.

 

[Slobodan Brcin]

Hello Nikolai,

The EWF partition is been created and image starts from the hdd *only*
if I *switched off HyperThreading* and left 1 CPU. In this case all
works. I mean ewgmgr shows partition, my apps running - OK.
When I switch on HyperThreading - I get BSOD 0x000000C2 (0x00000007,
0x00000CD4, 0x0, 0xF8990C4C). I switch HT off - all works.

So, as I see the problem arises when I have more than 1 CPU and EWF.

Has anybody succeeded with building ElTorito CD that works on a
multiprocessor PC?
Did MS test EWF on the ACPI Multiprocessor PC?

I'm not using ElTorito.

But I have successfully used EWF on Dual XEON P4-2400 machine.

Also I am using EWF with HTT Enabled on current device we are preparing.

So EWF is working on ACPI Multiprocessor PC?

At least in all my cases.


Best regards,
Slobodan

 

[Sean Liming \(eMVP\)]

Nikolai,

I am a little curios. I have XPe running on a Dual P3 machine with out
problems. Your system is dual XEON with Hyperthreading. Isn't the
Hyperthreading effect that a single physcial processor looks like two
virtual processors in the system? If you have two physical processors with
Hyperthreading, does that make the system look like it has 4 processors in
the system? The reason I curios is that XPe will only support 2 processor
out of the box, and don't know what effect Hyperthreading will have.

Regards,

Sean Liming
www.a7eng.com
Author: Windows NT Embedded Step-By-Step and XP Embedded Advanced.

 

[Gordon Smith \(eMVP\)]

I hate typos... Let's try that again.

Hyperthreading is 2 logical processors in one physical CPU. The OS doesn't
distinguish though. Since XP only supports 2 processors, that means you can
have one physical CPU with hyperthreading (thus 2 processors) or two
physical CPUs without hyperthreading (thus 2 processors).

If you have a system with 2 hyperthreading CPUs (thus 4 processors), XP will
only enumerate 2 of them. Which 2 is upto your BIOS. Typically, its going
to be the 1st logical processor in the first CPU and the 1st logical
processor in the second CPU.

 

[Slobodan Brcin]

Hi Gordon,
I don't have four processors but I'm very curious about this feature.

What do you think about statement from Nikolai?

If you have a system with 2 hyperthreading CPUs (thus 4 processors), XP will
only enumerate 2 of them. Which 2 is upto your BIOS. Typically, its going
to be the 1st logical processor in the first CPU and the 1st logical
processor in the second CPU.

Best regards,
Slobodan Brcin

 

[Gordon Smith \(eMVP\)]

I'd want someone from Microsoft to validate since I haven't personally
tested it but I'm assuming that the failure he's seeing is due to XP finding

2 processors. Maybe he ran TAP.exe without hyperthreading enabled and thus

the system he built didn't have a multiproc hal included.

 

[Slobodan Brcin]

I'd want someone from Microsoft to validate since I haven't personally

tested it but I'm assuming that the failure he's seeing is due to XP finding thus
the system he built didn't have a multiproc hal included.

Well if I understood correctly he explicitly said that in some build he can
see 2(4) processors, maybe I am wrong in interpreting this.

I have always assumed that Windows XP Home was meant for only one processor,
Although I can't remember where I have read that.
But it is working with HTT and I can see two processors.

So maybe it is same situation with Windows XP Professional, instead of two
you can use four processors in HTT case. Don't know.


Best regards,
Slobodan

 

[Sean Liming \(eMVP\)]

Hyperthreading sounds really cool, but how does it play against the
limitation that XPe can only support upto two processors. MS or Intel should
be able to answer this issue. If I have a chance I will check out El-Torito
booting from my Dual P3.

Sean

 

[Gordon Smith \(eMVP\)]

In the current set of OSes from Microsoft, each logical processor counts as
a processor towards its total count. The OS doesn't distinguish. The OS
enumerates processors from the BIOS - the BIOS is simply listing them all.

If you have a 2 CPU system (C1 and C2) each with hyperthreading then the
processors are reported to the OS in this order:

C1.first
C2.first
C1.second
C2.second

At least on the systems I've dealt with.

--Gordon

 

[Slobodan Brcin]

Hi Gordon,

On Windows XP Home I confirm that you can use HTT and see two processors.
What is the difference between Windows Home and Professional, in max
processor count?

To Nikolai,
If you are reading this could you confirm or deny that you are seeing four
procesors?



Best regards,
Slobodan

 

[Nikolai Vorontsov]

Hi, Sean and Gordon!

I am a little curios. I have XPe running on a Dual P3 machine with out
problems. Your system is dual XEON with Hyperthreading. Isn't the
Hyperthreading effect that a single physcial processor looks like two
virtual processors in the system? If you have two physical processors with
Hyperthreading, does that make the system look like it has 4 processors in
the system? The reason I curios is that XPe will only support 2 processor
out of the box, and don't know what effect Hyperthreading will have.

So, XPe supports at least 2 real CPUs and 4 HT logical ones. I can send
you a screen-shot, but you can believe me
I'm not sure that XPe supports 4 *real* CPUs - as I have no this machine
to test, but I guess that it does.

My problem is that XPe works OK on my machine, but EWF ElTorito CD
doesn't work... I suppose EWF problem...

For the ElTorito I use the same HAL and all drivers as for the standard
build. I'll try to just add EWF to my build...

 

[Arya Abraham]

This is probably a dead thread by now, but since, for
once, I feel that I can contribute to the group, I shall
add my two bits.

Windows until and including W2k counts each virtual/real
processor against the total in the license (which is 2 for
Win2k Professional). If you had two hyperthreading
processors, it would take one virtual PE from each real
processor. If you had only one hyperthreading processor,
you would see 2 processors.

WinXP understands that the virtual processors exist in
pairs on physical processors. Only physical processors
count to the limit in the license (at least 2 I would
think). If you use hyperthreading, the extra processors
were a bonus. So you could have a 2 processor license but
have 4 processor show up in the task manager (2 physical
processors).

-- Arya

 

[Slobodan Brcin]

Just for the reference,

This doc explains everything related to HTT and max number of processors.
http://www.microsoft.com/whdc/hwdev/platform/proc/ht-windows.mspx