From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ulrich Drepper Subject: Re: KVM Processor cache size Date: Mon, 02 Aug 2010 06:49:47 -0700 Message-ID: <4C56CCFB.204@redhat.com> References: <4C56BF6F.9040402@amd.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Ricardo Martins , "kvm@vger.kernel.org" To: Andre Przywara Return-path: Received: from mx1.redhat.com ([209.132.183.28]:37953 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753159Ab0HBNtu (ORCPT ); Mon, 2 Aug 2010 09:49:50 -0400 In-Reply-To: <4C56BF6F.9040402@amd.com> Sender: kvm-owner@vger.kernel.org List-ID: -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 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 curi= osity? 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. - --=20 =E2=9E=A7 Ulrich Drepper =E2=9E=A7 Red Hat, Inc. =E2=9E=A7 444 Castro S= t =E2=9E=A7 Mountain View, CA =E2=9D=96 -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.14 (GNU/Linux) iEYEARECAAYFAkxWzPsACgkQ2ijCOnn/RHQ2JwCeJsgXHxkWG/PYS8JQRiGM1UFF m78Ani9kmnKJyru/wh764NSgHSQx+WjU =3D6qet -----END PGP SIGNATURE-----