There are documented interfaces to get notifications from the system that paged or non-paged pool are becoming depleted or have been replenished relative to system-defined high memory or low memory amounts. See ?Standard Event Objects? in the WDK documentation.
If the OP was really looking for hints that the system is low (or not) on pool memory, those should be used ? e.g. as a hint to free cached resources that aren?t critically needed for operation on low memory conditions.
- S
From: xxxxx@lists.osr.com [mailto:xxxxx@lists.osr.com] On Behalf Of Prokash Sinha
Sent: Saturday, May 16, 2009 1:17 PM
To: Windows System Software Devs Interest List
Subject: Re: [ntdev] How to determine the maximum and currently-used paged pool size
Okay, I hate to see this goes on and on first because OP was really looking for global variables that would give him an indications within the next epoch (s)he is ready to go and grab or go and release the memory…
As few people pointed out there is no bullet proof method to do that, and I suspect OP also does not have that requirement. Otherwise OP would have go to the modeling it, rather than asking how it could be done by the driver.
For the sake of argument, lets say OP is in fact getting to know some estimated value within the next epoch ( let say within 10 ms on an average ). What are the approaches … ( For now ignore the UM & KM & HW )
(1) Well, differential equations is one approach. But we need a set of functionals that can easily form into DE and solve it by discretizing or whatever transform you can use. Big big question is what is the functional form to being with? I don’t have a clue …
(2) Well, it can be done by a simple statistical analysis: Mean and Sigma. Sure but what is the sample, what is the sample distribution. Again I sure don’t have a clue…
(3) What the problem signals to us?
A) We don’t know the shit, and it is random
B) What random? Random means nothing a functional form whose image domain is [0, 1]
C) Anything more? Of course there is some more … It is a continuous time and discrete state Random Process !.
D) That it?? Nope, this does not have a memory so (i) we don’t know when the next ( + or - ) consumptions are going to be. Oh, the inter arrival time is memory less. So it is exponential.
E) How about the payload ( + or - ) of the consumptions? Same thing as the along the time line.
Rest we talked about in this forum before … And quite unnecessary, until OP comes and say I want the model and say "Pro I know you did some mathematical modeling in the past, but sure hell you are an ugly model when I look at your face and compare with the pretty faces in the modeling business 
-pro
On Sat, May 16, 2009 at 12:17 PM, > wrote:
> I have every reason to believe that Calvin’s estimation based approach to determining the
> size of paged pool would yield a very satisfactory result. I suspect it would be not that much more
> state intensive nor complex than a good ‘peak/average’ estimator typical of network (or disk)
> throughput statistics - something found in kernel modes the world over (and in hardware too).
Please note that the things you have mentioned don’t require solving differential equations - all they need is a relatively simple statistical analysis like calculating mean and standard deviation. Therefore, Calvin’s post made me suspect that he would rather go for something significantly more complex than that
(for example, Fourier Transform)…
Anton Bassov
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