topic Windows WMI Win32_CacheMemory class - cache Associativity value in Software Tuning, Performance Optimization & Platform Monitoring

Windows WMI Win32_CacheMemory class - cache Associativity values

nrcaliendo — Mon, 25 Jun 2012 12:42:13 GMT

I hope this is the right forum for this thread, it was the closest matchI could find...

I already posted this question on Microsoft's MSDN forum, and they recommended coming here.

I'm querying the Win32_CacheMemory class to enumerate my CPU cache. I'm getting a value of 9 back for Associativity. All online documentation I can find only lists values 1-8.

I'm trying to find info on full set ofpossible values.

My system:

Intel Core i5-2540M CPU @ 2.60 GHz
Windows 7 Pro 64-bit

Windows WMI Win32_CacheMemory class - cache Associativity value

SergeyKostrov — Wed, 27 Jun 2012 01:25:57 GMT

Quoting nrcaliendo

...I already posted this question on Microsoft's MSDN forum, and they recommended coming here.

[SergeyK]That is really strange that nobody from Microsoft couldn't answer your question...

I'm querying the Win32_CacheMemory class to enumerate my CPU cache...

In what WMI namespace is it?

Best regards,
Sergey

Windows WMI Win32_CacheMemory class - cache Associativity value

SergeyKostrov — Wed, 27 Jun 2012 04:45:00 GMT

Quoting nrcaliendo

I'm querying the Win32_CacheMemory class to enumerate my CPU cache. I'm getting a value of 9 back for Associativity. All online documentation I can find only lists values 1-8.

I'm trying to find info on full set ofpossible values...

Please take a look at:

1. Intel Software Developer's Manual - Instruction Set Reference (A-M) Vol 2A

Table 3-20

A. It looks like9 is a'Fully Associative' and Intel coded it with a value 0FH. By some reason Microsoft's
WMI uses the value 9 instead.

B.Could itbe'Reserved'?

2. CPUID instruction
EAX = 4
EBX = Bits 31-22W - Ways of Associativity

Windows WMI Win32_CacheMemory class - cache Associativity value

SergeyKostrov — Wed, 27 Jun 2012 23:37:14 GMT

Quoting nrcaliendo
I'm querying the Win32_CacheMemory class to enumerate my CPU cache...

>>In what WMI namespace is it?

I figured it out: it is the classin CIMV2 namespace.

Windows WMI Win32_CacheMemory class - cache Associativity value

SergeyKostrov — Thu, 28 Jun 2012 00:12:18 GMT

Quoting Sergey Kostrov

Quoting nrcaliendo
I'm querying the Win32_CacheMemory class to enumerate my CPU cache. I'm getting a value of 9 back for Associativity. All online documentation I can find only lists values 1-8.

I'm trying to find info on full set ofpossible values...

Please take a look at:

1. Intel Software Developer's Manual - Instruction Set Reference (A-M) Vol 2A

You can find lots of Intel manuals here:

http://www.intel.com/content/www/us/en/processors/architectures-software-developer-manuals.html?wapkw=Manuals

Windows WMI Win32_CacheMemory class - cache Associativity value

nrcaliendo — Thu, 28 Jun 2012 12:35:34 GMT

Thank you for the information. I reposted back on Microsoft's forum.

There does not appear to be an equivalency between what Intel returns (CPUID instruction) and what WMI returns.

WMI just returnsthe ordinal numberof the associativity type within an enumeration.

CPUID	WMI
00H - Disabled 01H - Direct mapped 02H - 2-way 04H - 4-way 06H - 8-way 08H - 16-way 0FH - Fully associative	1 - Other 2 - Unknown 3 - Direct Mapped 4 - 2-way Set-Associative 5 - 4-way Set-Associative 6 - Fully Associative 7 - 8-way Set Associative 8 - 16-way Set-Associative

Windows WMI Win32_CacheMemory class - cache Associativity value

SergeyKostrov — Thu, 28 Jun 2012 23:13:27 GMT

How did you get WMI numbers? From a header file? From a TLB-library?

Windows WMI Win32_CacheMemory class - cache Associativity value

SergeyKostrov — Fri, 29 Jun 2012 01:07:37 GMT

Quoting Sergey Kostrov

...
A. It looks like9 is a'Fully Associative' and Intel coded it with a value 0FH. By some reason Microsoft's
WMI uses the value 9 instead.
...

Not confirmed. Please see Post #5.