From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH v2 2/3] KVM: Use -cpu best as default on x86 Date: Mon, 02 Jul 2012 17:27:04 +0300 Message-ID: <4FF1AFB8.3090904@redhat.com> References: <1340728795-4379-1-git-send-email-agraf@suse.de> <1340728795-4379-2-git-send-email-agraf@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: qemu-devel qemu-devel , KVM list , Ryan Harper , Anthony Liguori To: Alexander Graf Return-path: Received: from mx1.redhat.com ([209.132.183.28]:15820 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751028Ab2GBO1O (ORCPT ); Mon, 2 Jul 2012 10:27:14 -0400 In-Reply-To: <1340728795-4379-2-git-send-email-agraf@suse.de> Sender: kvm-owner@vger.kernel.org List-ID: On 06/26/2012 07:39 PM, Alexander Graf wrote: > When running QEMU without -cpu parameter, the user usually wants a sane > default. So far, we're using the qemu64/qemu32 CPU type, which basically > means "the maximum TCG can emulate". > > That's a really good default when using TCG, but when running with KVM > we much rather want a default saying "the maximum performance I can get". > > Fortunately we just added an option that gives us the best performance > while still staying safe on the testability side of things: -cpu best. > So all we need to do is make -cpu best the default when the user doesn't > explicitly specify a CPU type. > > This fixes a lot of subtile breakage in the GNU toolchain (libgmp) which subtle > hicks up on QEMU's non-existent CPU models. > > This patch also adds a new pc-1.2 machine type to stay backwards compatible > with older versions of QEMU. -- error compiling committee.c: too many arguments to function