From: Peter Lieven Subject: Re: win7 bad i/o performance, high insn_emulation and exists Date: Tue, 21 Feb 2012 11:59:23 +0100 Message-ID: <4F43790B.90603@dlh.net> References: <4F428E53.2010602@dlh.net> <20120220184008.GF29601@redhat.com> <20120220190449.GG29601@redhat.com> <4F42A62A.9080503@dlh.net> <20120220204515.GI29601@redhat.com> <4F437707.8070208@dlh.net> <20120221105615.GA27176@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org, vrozenfe@redhat.com To: Gleb Natapov Return-path: Received: from ssl.dlh.net ([91.198.192.8]:32996 "EHLO ssl.dlh.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754552Ab2BUK7Y (ORCPT ); Tue, 21 Feb 2012 05:59:24 -0500 In-Reply-To: <20120221105615.GA27176@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On 21.02.2012 11:56, Gleb Natapov wrote: > On Tue, Feb 21, 2012 at 11:50:47AM +0100, Peter Lieven wrote: >>> I hope it will make Windows use TSC instead, but you can't be sure >>> about anything with Windows :( >> Whatever it does now it eates more CPU has almost equal >> number of exits and throughput is about the same (15MB/s). >> If pmtimer is at 0xb008 it still reads it like hell. >> >> I checked with bcedit /v that useplatformclock is set to "No". > Yeah, today I noticed that it is likely virtio drivers that hammer > on PM timer (at least rip of the instruction that access it is > very close to rip of the instruction that access virtio pio). > Vadim, Windows driver developer, is CCed. Ok, I will switch to IDE and e1000 to confirm this? Or does it not make sense? Peter