Disabling virtual mem causes perf counters issues

[Dom]

Hi,

I'm running into problems with XP embedded (but also seen on all versions of
XP) when disabling virtual memory. It appears that CPU and Memory
performance counters are no longer accessible on the system, via perfos, pdh
or WMI. Perfos.dll has been disabled in the registry:

HKLM\SYSTEM\CurrentControlSet\Services\PerfOS\Performance\Disable
Performance Counters = 1.

These counters worked fine on Win2K and NT4 with VM disabled.
Doing a quick search reveals that other people are seeing the problem too:

http://groups.google.co.uk/groups?q...=off&[email protected]&rnum=1

The general consensus is its a bug in XP that is causing the counters in
perfos to crash, so the service dies and XP disables it

If I enable virtual memory the problem goes away, however this is not a
satisfactory solution for various reasons.

Anyone seen this before, or know if MS is working on a fix for it? I can't
see a mention of it on MSDN.

Thanks,

Dom

 

[Carey Frisch [MVP]]

Virtual Memory in Windows XP
http://aumha.org/win5/a/xpvm.php

Windows XP Memory Tweak guide
http://www.techspot.com/tweaks/memory-winxp/xpmem-3.shtml

--
Carey Frisch
Microsoft MVP
Windows XP - Shell/User

Be Smart! Protect your PC!
http://www.microsoft.com/security/protect/

--------------------------------------------------------------------------------------------


| Hi,
|
| I'm running into problems with XP embedded (but also seen on all versions of
| XP) when disabling virtual memory. It appears that CPU and Memory
| performance counters are no longer accessible on the system, via perfos, pdh
| or WMI. Perfos.dll has been disabled in the registry:
|
| HKLM\SYSTEM\CurrentControlSet\Services\PerfOS\Performance\Disable
| Performance Counters = 1.
|
| These counters worked fine on Win2K and NT4 with VM disabled.
| Doing a quick search reveals that other people are seeing the problem too:
|
|
http://groups.google.co.uk/groups?q...=off&[email protected]&rnum=1
|
| The general consensus is its a bug in XP that is causing the counters in
| perfos to crash, so the service dies and XP disables it
|
| If I enable virtual memory the problem goes away, however this is not a
| satisfactory solution for various reasons.
|
| Anyone seen this before, or know if MS is working on a fix for it? I can't
| see a mention of it on MSDN.
|
| Thanks,
|
| Dom

 

[Dom]

Thanks for those links, they tell me how to set up virtual memory, and what
it is - however this I already know.
What I want to know is why, if I disable virtual memory (i.e. set the
pagefile to 0K), does XP automatically disable the counters handled by
perfos.dll? (memory, cpu etc..)
This seems to me to be a bug. I have recieved a reply in the XP embedded
group which kind of backs up my theory.

Unfortunately it looks like i'll have to wait until Longhorn is released
until its fixed....

 

[Carey Frisch [MVP]]

Windows XP requires the use of Virtual Memory to perform properly.
XP is a Virtual Memory Operating System and there is nothing you
can do to prevent Virtual Memory in the NT kernel.

Understanding Virtual Memory
http://www.tweakhound.com/xp/virtualmemory.htm

Memory Support and Windows Operating Systems
http://www.microsoft.com/whdc/system/platform/server/PAE/PAEmem.mspx

Kernel Enhancements in Windows XP
http://www.microsoft.com/whdc/driver/kernel/XP_kernel.mspx

--
Carey Frisch
Microsoft MVP
Windows XP - Shell/User

Be Smart! Protect your PC!
http://www.microsoft.com/security/protect/

------------------------------------------------------------------------------------------


| Thanks for those links, they tell me how to set up virtual memory, and what
| it is - however this I already know.
| What I want to know is why, if I disable virtual memory (i.e. set the
| pagefile to 0K), does XP automatically disable the counters handled by
| perfos.dll? (memory, cpu etc..)
| This seems to me to be a bug. I have recieved a reply in the XP embedded
| group which kind of backs up my theory.
|
| Unfortunately it looks like i'll have to wait until Longhorn is released
| until its fixed....