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Re: cpuinfo cache size




On 8/3/2015 12:15 PM, Achim Gratz wrote:
Corinna Vinschen <corinna-cygwin <at> cygwin.com> writes:
Cygwin is lacking the code to fetch L3 caches and afaics, it's not
overly simple.  At least calling cpuid as for L1 and L2 caches is not
sufficient, apparently.

If you can use the Windows API, then this
https://msdn.microsoft.com/en-us/library/ms683194.aspx

Should be possible to have both info available ?
Any idea how to obtain the other cache infos ?

Not completely.  You have to use different cpuid codes for AMD and Intel
CPUs, and you have to call cpuid multiple times to get the full info
for all L3 caches of the system's CPUs, but I'm fuzzy on the details.

I have no patches, but another difference to Linux is that the CPU frequency
reported is the maximum (non-turbo) frequency instead of the actual one
(which could be larger or lower depending on the frequency scaling in
effect).  That seems to require more infrastructure, though.

I solved packing HWLOC

http://www.open-mpi.org/projects/hwloc/

It provide the same info in a simpler way

Regards,
Achim.


Regards
Marco


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