PagedPoolSize and Performance question

[Tommy]

I just increased the memory on my XP box to 2GB. I'm reading this
performance tunning article at:

http://www.windowsitlibrary.com/Content/69/06/1.html

and regarding items V1-6 and V1-7, specifically regarding
NonPagedPoolSize and PagedPoolSize, it says:

VI-6 NT categorizes memory as either paged or nonpaged. Paged
memory holds data that can temporarily be moved from physical
memory to the system's paging file if space is needed for
different data in physical memory. Nonpaged memory stores data
that must be present in physical memory at all times. NT
allocates a portion of physical memory for nonpaged memory
when the system starts up, and this allocation can't grow. If
drivers or NT exhaust this storage, the system may become
unstable or operations may start to fail. Modifying these two
registry entries lets you override the defaults set for the
paged and nonpaged pools.

Hive: HKEY_LOCAL_MACHINE
Key: System\CurrentControlSet\Control\Session Manager\
Memory Management
Value Name: NonPagedPoolSize
Data Type: REG_DWORD
Value: <number in bytes >

This value is the number of bytes of physical memory you want to
allocate for nonpaged memory. To monitor your memory, use
Performance Monitor to watch the percentage of committed memory
that's used. If more than 80 percent of memory is used
consistently, you should increase this value. Likewise, if the
system's nonpaged memory usage is low, reducing the amount
allocated for it increases system performance.

VI-7 Hive: HKEY_LOCAL_MACHINE
Key: System\CurrentControlSet\Control
\Session Manager\Memory Management
Value Name: PagedPoolSize
Data Type: REG_DWORD
Value: <number in bytes >

This value is the number of bytes in the paged memory pool. It
overrides the system’s default calculation, which is roughly equal
to the physical memory on Workstation and a minimum of 50 MB on
Server. Paged pool is different from virtual memory size — the paged
pool is space reserved in the system’s virtual memory map for NT and
device drivers to allocate pageable data.

You can monitor the amount of paged pool the system uses with the
Performance Monitor, which also shows the maximum allocation
possible. If the amount of memory used is consistently more than 80
percent, you should use this setting to override the default.

On my machine, I am seeing at a given moment in time:

Kernel Memory (K)
Total 59008
Paged 50968 <--- 87%
Nonpaged 8040

Is that what it is referencing too? If so, do you have an idea on
what that it could be increased too? The NonPaged size seems pretty low.

Thanks

--

[Pavel A.]

The numbers you're seeing seem to be the currently
used counts, not the maximum size.
On my box with 2 GB RAM, the nonpaged pool usage
is currently ~ 16 MB and paged pool ~ 70 MB.
Use the perfmon tool, it has more memory stats and
a prettier GUI.

--PA

[Tommy]

Pavel, do you have the specific counter names I can use here?

Thanks

[Pavel A.]

Tommy wrote:
> Pavel, do you have the specific counter names I can use here?

Memory\Pool Paged Bytes
Memory\Pool Nonpaged Bytes
Memory\System Cache Resident Bytes

etc.

--PA

[Tommy]

Thanks Pavel.

These I have and these match the kernel paged, non paged as shown in
task man.

What I was looking for in regards to the article V1-6, V1-7 is that
the registry values is in bytes, but it mentions a percentage to match
file. 80% Percentage of what? Of the total combined?

What I am seeing is 87% kernel paged size on my XP box with 2GB, an
even split of 50% for the paged and non-paged on my 1GB Windows 2003
server box.

Overall, on this XP box with its 2GB ram increase, I am still trying
see why there seems to be an more than necessary page faults,
especially for the VS2005 processes loaded.

I see at this msdn blog link what the typical automatic settings are
for paged and non page pool sizes dependng on the OS and /3GB switch

http://blogs.technet.com/askperf/archive/2007/03/07/memory-management-understanding-pool-resources.aspx

I'm just wondering if I already have the "best" of this machine
performance by tuning it as much as I can. :-)

I already turned off the XP graphics on it and that helps
tremendously. Looks like 2000/2003 now :-)

--

[Pavel A.]

Tommy wrote:
> Thanks Pavel.
>
> These I have and these match the kernel paged, non paged as shown in
> task man.
>
> What I was looking for in regards to the article V1-6, V1-7 is that the
> registry values is in bytes, but it mentions a percentage to match
> file. 80% Percentage of what? Of the total combined?

The percents are just relative
to the perfmon chart scale, that it perhaps chooses automatically.
The numbers are in bytes, you can see them under the chart.

-pa

[Günter Prossliner]

Hello Tommy!

> Overall, on this XP box with its 2GB ram increase, I am still trying

> see why there seems to be an more than necessary page faults,...

How do you meause the page-faults?

Do not use taskmgr for that, because it includes also the soft faults
(mostly referencing system cached pages on the standby list), which are not
really paged out.

Use on of the Counters:

Memory: Pages / esc
Memory: Pages Input / sec
Memory: Pages Output / sec

GP