Disabling Virtual Memory causes perf counter problems

[Dom]

Hi,

I'm running into problems with XP embedded 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

 

[Andy Allred [MS]]

This had been discussed before in the newsgroups (check Google Archives
for questions). Here is the gist of it, though this should be addressed
for Longhorn:
PerfMon has a dependency on the presence of a pagefile. Without the
pagefile you will be missing counters for the following: Cache, Memory,
Objects, Processor and System.
Workaround: Add pagefile support for a pagefile of at least 2MB. Set
Min = 2MB & set Max = 2MB.

 

[Dom]

Thanks for the reply - I have a couple more questions regarding this:

If we set the pagefile to 2MB, and never allocate more memory than we have
in RAM, will it ever get used? If so under what circumstances?

We're also worried about pagefile corruption on hard reset, if the CPU board
is resetted, what are the chances of the pagefile getting corrupted and
causing XP not to boot?
Are there any things we can do to guard against this?

Many Thanks for your help,
Dom