Pool sizes in NT

NTDEV
1

Hi all,

I’m looking for documentation about the size of the pools in various
versions of NT (from 4 to 6 I’d say).

Especially I would like to know what is the size of NonPagedPoolMustSucceed

The reason why I ask this is because GlobalMemoryStatus(Ex), the user API
doesn’t return all the actual physical memory, and I think this is because
some of the physical memory is reserved in a special pool and not accounted
at all.

Any hint would be great.

Thanks in advance.

–

Edouard Alligand

2

NonPagedPoolMustSucceed used to be tiny, a few pages IIRC.

–
Don Burn (MVP, Windows DDK)
Windows 2k/XP/2k3 Filesystem and Driver Consulting
Website: http://www.windrvr.com
Blog: http://msmvps.com/blogs/WinDrvr
Remove StopSpam to reply

“Edouard A.” wrote in message news:xxxxx@ntdev…
> Hi all,
>
>
>
> I’m looking for documentation about the size of the pools in various
> versions of NT (from 4 to 6 I’d say).
>
>
>
> Especially I would like to know what is the size of
> NonPagedPoolMustSucceed
>
>
>
> The reason why I ask this is because GlobalMemoryStatus(Ex), the user API
> doesn’t return all the actual physical memory, and I think this is because
> some of the physical memory is reserved in a special pool and not
> accounted
> at all.
>
>
>
> Any hint would be great.
>
>
>
> Thanks in advance.
>
>
>
>
>
> –
>
>
>
> Edouard Alligand
>
>

3

Mmm… If you’re right that doesn’t explain why you could get up to 512 kb
of difference between GlobalMemoryStatus and real account of physical
memory…

-----Original Message-----
From: xxxxx@lists.osr.com [mailto:bounce-305608-
xxxxx@lists.osr.com] On Behalf Of Don Burn
Sent: vendredi 9 novembre 2007 20:33
To: Windows System Software Devs Interest List
Subject: Re:[ntdev] Pool sizes in NT

NonPagedPoolMustSucceed used to be tiny, a few pages IIRC.

–
Don Burn (MVP, Windows DDK)
Windows 2k/XP/2k3 Filesystem and Driver Consulting
Website: http://www.windrvr.com
Blog: http://msmvps.com/blogs/WinDrvr
Remove StopSpam to reply

“Edouard A.” wrote in message news:xxxxx@ntdev…
> > Hi all,
> >
> >
> >
> > I’m looking for documentation about the size of the pools in various
> > versions of NT (from 4 to 6 I’d say).
> >
> >
> >
> > Especially I would like to know what is the size of
> > NonPagedPoolMustSucceed
> >
> >
> >
> > The reason why I ask this is because GlobalMemoryStatus(Ex), the user
> API
> > doesn’t return all the actual physical memory, and I think this is
> because
> > some of the physical memory is reserved in a special pool and not
> > accounted
> > at all.
> >
> >
> >
> > Any hint would be great.
> >
> >
> >
> > Thanks in advance.
> >
> >
> >
> >
> >
> > –
> >
> >
> >
> > Edouard Alligand
> >
> >
>
>
>
> —
> NTDEV is sponsored by OSR
>
> For our schedule of WDF, WDM, debugging and other seminars visit:
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> To unsubscribe, visit the List Server section of OSR Online at
> http://www.osronline.com/page.cfm?name=ListServer

4

Hello,

this article has some answers:
http://msdn2.microsoft.com/en-us/library/aa366778.aspx

5

Edouard A. wrote:

I’m looking for documentation about the size of the pools in various
versions of NT (from 4 to 6 I’d say).

Especially I would like to know what is the size of
*NonPagedPoolMustSucceed*

The reason why I ask this is because GlobalMemoryStatus(Ex), the user
API doesn’t return all the actual physical memory, and I think this is
because some of the physical memory is reserved in a special pool and
not accounted at all.

Any hint would be great.

How far off is it? I’d be much more inclined to think it was the UMA
space for your graphics card, or some memory reserved by the SMBIOS.
That is, someone is lying to Windows, who then reports it to you.

–
Tim Roberts, xxxxx@probo.com
Providenza & Boekelheide, Inc.

6

Must-succeed pool is obsolete since w2k.

The reason is that allocation failure from must-succeed pool is a BSOD
and cannot be handled by the caller.

The presence of such feature in older Windows is just plain a misdesign.

–
Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation
xxxxx@storagecraft.com
http://www.storagecraft.com

“Edouard A.” wrote in message news:xxxxx@ntdev…
> Hi all,
>
>
>
> I’m looking for documentation about the size of the pools in various
> versions of NT (from 4 to 6 I’d say).
>
>
>
> Especially I would like to know what is the size of NonPagedPoolMustSucceed
>
>
>
> The reason why I ask this is because GlobalMemoryStatus(Ex), the user API
> doesn’t return all the actual physical memory, and I think this is because
> some of the physical memory is reserved in a special pool and not accounted
> at all.
>
>
>
> Any hint would be great.
>
>
>
> Thanks in advance.
>
>
>
>
>
> –
>
>
>
> Edouard Alligand
>
>