From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752878Ab2FSFIF (ORCPT ); Tue, 19 Jun 2012 01:08:05 -0400 Received: from mx1.redhat.com ([209.132.183.28]:21665 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751809Ab2FSFIE (ORCPT ); Tue, 19 Jun 2012 01:08:04 -0400 Message-ID: <4FDFFEF8.9000609@redhat.com> Date: Tue, 19 Jun 2012 12:24:24 +0800 From: Asias He User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:13.0) Gecko/20120605 Thunderbird/13.0 MIME-Version: 1.0 To: Stefan Hajnoczi CC: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: Re: [PATCH v2 0/3] Improve virtio-blk performance References: <1340002390-3950-1-git-send-email-asias@redhat.com> <4FDEF73E.3010501@redhat.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/18/2012 06:58 PM, Stefan Hajnoczi wrote: > As long as the latency is decreasing that's good. But It's worth > keeping in mind that these percentages are probably wildly different > on real storage devices and/or qemu-kvm. What we don't know here is > whether this bottleneck matters in real environments - results with > real storage and with qemu-kvm would be interesting. Yes. Here is the performance data on a Fusion-IO SSD device. Fio test is performed in a 8 vcpu guest with Fusion-IO based guest using kvm tool. Short version: With bio-based IO path, sequential read/write, random read/write IOPS boost : 11%, 11%, 13%, 10% Latency improvement: 10%, 10%, 12%, 10% Long Version: With bio-based IO path: read : io=2048.0MB, bw=58920KB/s, iops=117840 , runt= 35593msec write: io=2048.0MB, bw=64308KB/s, iops=128616 , runt= 32611msec read : io=3095.7MB, bw=59633KB/s, iops=119266 , runt= 53157msec write: io=3095.7MB, bw=62993KB/s, iops=125985 , runt= 50322msec clat (usec): min=0 , max=1284.3K, avg=128109.01, stdev=71513.29 clat (usec): min=94 , max=962339 , avg=116832.95, stdev=65836.80 clat (usec): min=0 , max=1846.6K, avg=128509.99, stdev=89575.07 clat (usec): min=0 , max=2256.4K, avg=121361.84, stdev=82747.25 cpu : usr=56.79%, sys=421.70%, ctx=147335118, majf=21080, minf=19852517 cpu : usr=61.81%, sys=455.53%, ctx=143269950, majf=16027, minf=24800604 cpu : usr=63.10%, sys=455.38%, ctx=178373538, majf=16958, minf=24822612 cpu : usr=62.04%, sys=453.58%, ctx=226902362, majf=16089, minf=23278105 With request-based IO path: read : io=2048.0MB, bw=52896KB/s, iops=105791 , runt= 39647msec write: io=2048.0MB, bw=57856KB/s, iops=115711 , runt= 36248msec read : io=3095.7MB, bw=52387KB/s, iops=104773 , runt= 60510msec write: io=3095.7MB, bw=57310KB/s, iops=114619 , runt= 55312msec clat (usec): min=0 , max=1532.6K, avg=142085.62, stdev=109196.84 clat (usec): min=0 , max=1487.4K, avg=129110.71, stdev=114973.64 clat (usec): min=0 , max=1388.6K, avg=145049.22, stdev=107232.55 clat (usec): min=0 , max=1465.9K, avg=133585.67, stdev=110322.95 cpu : usr=44.08%, sys=590.71%, ctx=451812322, majf=14841, minf=17648641 cpu : usr=48.73%, sys=610.78%, ctx=418953997, majf=22164, minf=26850689 cpu : usr=45.58%, sys=581.16%, ctx=714079216, majf=21497, minf=22558223 cpu : usr=48.40%, sys=599.65%, ctx=656089423, majf=16393, minf=23824409 -- Asias From mboxrd@z Thu Jan 1 00:00:00 1970 From: Asias He Subject: Re: [PATCH v2 0/3] Improve virtio-blk performance Date: Tue, 19 Jun 2012 12:24:24 +0800 Message-ID: <4FDFFEF8.9000609@redhat.com> References: <1340002390-3950-1-git-send-email-asias@redhat.com> <4FDEF73E.3010501@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org To: Stefan Hajnoczi Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org List-Id: kvm.vger.kernel.org On 06/18/2012 06:58 PM, Stefan Hajnoczi wrote: > As long as the latency is decreasing that's good. But It's worth > keeping in mind that these percentages are probably wildly different > on real storage devices and/or qemu-kvm. What we don't know here is > whether this bottleneck matters in real environments - results with > real storage and with qemu-kvm would be interesting. Yes. Here is the performance data on a Fusion-IO SSD device. Fio test is performed in a 8 vcpu guest with Fusion-IO based guest using kvm tool. Short version: With bio-based IO path, sequential read/write, random read/write IOPS boost : 11%, 11%, 13%, 10% Latency improvement: 10%, 10%, 12%, 10% Long Version: With bio-based IO path: read : io=2048.0MB, bw=58920KB/s, iops=117840 , runt= 35593msec write: io=2048.0MB, bw=64308KB/s, iops=128616 , runt= 32611msec read : io=3095.7MB, bw=59633KB/s, iops=119266 , runt= 53157msec write: io=3095.7MB, bw=62993KB/s, iops=125985 , runt= 50322msec clat (usec): min=0 , max=1284.3K, avg=128109.01, stdev=71513.29 clat (usec): min=94 , max=962339 , avg=116832.95, stdev=65836.80 clat (usec): min=0 , max=1846.6K, avg=128509.99, stdev=89575.07 clat (usec): min=0 , max=2256.4K, avg=121361.84, stdev=82747.25 cpu : usr=56.79%, sys=421.70%, ctx=147335118, majf=21080, minf=19852517 cpu : usr=61.81%, sys=455.53%, ctx=143269950, majf=16027, minf=24800604 cpu : usr=63.10%, sys=455.38%, ctx=178373538, majf=16958, minf=24822612 cpu : usr=62.04%, sys=453.58%, ctx=226902362, majf=16089, minf=23278105 With request-based IO path: read : io=2048.0MB, bw=52896KB/s, iops=105791 , runt= 39647msec write: io=2048.0MB, bw=57856KB/s, iops=115711 , runt= 36248msec read : io=3095.7MB, bw=52387KB/s, iops=104773 , runt= 60510msec write: io=3095.7MB, bw=57310KB/s, iops=114619 , runt= 55312msec clat (usec): min=0 , max=1532.6K, avg=142085.62, stdev=109196.84 clat (usec): min=0 , max=1487.4K, avg=129110.71, stdev=114973.64 clat (usec): min=0 , max=1388.6K, avg=145049.22, stdev=107232.55 clat (usec): min=0 , max=1465.9K, avg=133585.67, stdev=110322.95 cpu : usr=44.08%, sys=590.71%, ctx=451812322, majf=14841, minf=17648641 cpu : usr=48.73%, sys=610.78%, ctx=418953997, majf=22164, minf=26850689 cpu : usr=45.58%, sys=581.16%, ctx=714079216, majf=21497, minf=22558223 cpu : usr=48.40%, sys=599.65%, ctx=656089423, majf=16393, minf=23824409 -- Asias