How to determine the L2 cache size on non-AMD CPUs (automatic page queue color tuning)?

John Polstra jdp at
Wed Jun 16 16:36:06 GMT 2004

On 16-Jun-2004 Radek Kozlowski wrote:
> On 2004.06.16 18:11, John Polstra wrote:
>> Check out the "misc/cpuid" port.  Here's some sample output from a
>> PIII system.  Cache information is at the end.
> The latest version of cpuid is from 2002 and at least for my Athlon XP-M 
> processor it doesn't read the information about L2 cache correctly. 
> IIRC, for my L2 size it only takes one byte from the beginning of ecx 
> register, whereas in my case it is stored in two, a.s.o. So I wouldn't 
> rely on cpuid when it comes to newer CPUs.

Yes, but it gives working code that generally shows how to get the
information.  Here's a link to an Intel document "Intel(R) Processor
Idientification and the CPUID Instruction" that covers the newer CPUs:


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