Re: KVM Processor cache size

Ricardo Martins
2010-08-02T18:38:41Z

Thanks for the answers...

I am creating an environment with multiple virtual servers, my main
concern is whether I have a noticeable
loss of performance because of this problem, if the answer is yes I
will find another solution for my host server.

2010/8/2 Ulrich Drepper <drepper@redhat.com>:
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> On 08/02/2010 05:51 AM, Andre Przywara wrote:
>> Do you have a use case for the cache size or is this just out of curiosity?
>
> glibc uses the cache size information returned by cpuid to perform
> optimizations.  For instance, copy operations which would pollute too
> much of the cache because they are large will use non-temporal
> instructions.  There are real performance benefits.  Even the synthetic
> CPU provided by qemu should have a more realistic value.
>
> - --
> ➧ Ulrich Drepper ➧ Red Hat, Inc. ➧ 444 Castro St ➧ Mountain View, CA ❖
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