From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57250) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YiIVx-0008D3-E7 for qemu-devel@nongnu.org; Wed, 15 Apr 2015 04:17:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YiIVu-0006mZ-8V for qemu-devel@nongnu.org; Wed, 15 Apr 2015 04:17:41 -0400 Received: from mail-la0-f54.google.com ([209.85.215.54]:35919) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YiIVt-0006mN-TZ for qemu-devel@nongnu.org; Wed, 15 Apr 2015 04:17:38 -0400 Received: by lagv1 with SMTP id v1so26819526lag.3 for ; Wed, 15 Apr 2015 01:17:36 -0700 (PDT) Received: from [192.168.1.184] ([31.28.11.22]) by mx.google.com with ESMTPSA id cb5sm774404lad.21.2015.04.15.01.17.35 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 15 Apr 2015 01:17:35 -0700 (PDT) Message-ID: <552E1EB4.3030805@clodo.ru> Date: Wed, 15 Apr 2015 11:17:56 +0300 From: Konstantin Krotov MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] virtio-blk and virtio-scsi performance comparison List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Hello list! I performed tests with fio and obtained results: *** virtio-scsi with cache=none, io=threads, blok device is md-device from mdadm raid1, random r/w, 32 thread from guest (debian, kernel 3.16): fio fio1 readtest: (g=0): rw=randrw, bs=4K-4K/4K-4K/4K-4K, ioengine=libaio, iodepth=32 fio-2.1.11 Starting 1 process Jobs: 1 (f=1): [m(1)] [100.0% done] [126.2MB/125.1MB/0KB /s] [32.3K/32.3K/0 iops] [eta 00m:00s] readtest: (groupid=0, jobs=1): err= 0: pid=707: Wed Apr 8 07:35:01 2015 read : io=5117.4MB, bw=125830KB/s, iops=31457, runt= 41645msec slat (usec): min=4, max=343, avg=11.45, stdev=10.24 clat (usec): min=104, max=16667, avg=484.09, stdev=121.96 lat (usec): min=112, max=16672, avg=495.90, stdev=123.67 clat percentiles (usec): | 1.00th=[ 302], 5.00th=[ 346], 10.00th=[ 374], 20.00th=[ 406], | 30.00th=[ 426], 40.00th=[ 446], 50.00th=[ 462], 60.00th=[ 482], | 70.00th=[ 506], 80.00th=[ 540], 90.00th=[ 596], 95.00th=[ 732], | 99.00th=[ 948], 99.50th=[ 996], 99.90th=[ 1176], 99.95th=[ 1240], | 99.99th=[ 1384] bw (KB /s): min=67392, max=135216, per=99.99%, avg=125813.01, stdev=12524.05 write: io=5114.7MB, bw=125763KB/s, iops=31440, runt= 41645msec slat (usec): min=4, max=388, avg=11.85, stdev=10.47 clat (usec): min=147, max=8968, avg=505.23, stdev=127.40 lat (usec): min=155, max=8973, avg=517.45, stdev=128.97 clat percentiles (usec): | 1.00th=[ 334], 5.00th=[ 370], 10.00th=[ 394], 20.00th=[ 426], | 30.00th=[ 446], 40.00th=[ 462], 50.00th=[ 478], 60.00th=[ 498], | 70.00th=[ 524], 80.00th=[ 556], 90.00th=[ 628], 95.00th=[ 756], | 99.00th=[ 988], 99.50th=[ 1064], 99.90th=[ 1288], 99.95th=[ 1368], | 99.99th=[ 2224] bw (KB /s): min=67904, max=136384, per=99.99%, avg=125746.89, stdev=12449.56 lat (usec) : 250=0.05%, 500=64.27%, 750=30.80%, 1000=4.20% lat (msec) : 2=0.67%, 4=0.01%, 10=0.01%, 20=0.01% cpu : usr=18.03%, sys=76.42%, ctx=26617, majf=0, minf=7 IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=100.0%, >=64=0.0% submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0% complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.1%, 64=0.0%, >=64=0.0% issued : total=r=1310044/w=1309348/d=0, short=r=0/w=0/d=0 latency : target=0, window=0, percentile=100.00%, depth=32 Run status group 0 (all jobs): READ: io=5117.4MB, aggrb=125829KB/s, minb=125829KB/s, maxb=125829KB/s, mint=41645msec, maxt=41645msec WRITE: io=5114.7MB, aggrb=125762KB/s, minb=125762KB/s, maxb=125762KB/s, mint=41645msec, maxt=41645msec Disk stats (read/write): sda: ios=1302885/1302192, merge=55/0, ticks=281040/321660, in_queue=601264, util=99.29% same guest, *** virtio-blk with cache=none, io=threads, blok device is md-device from mdadm raid1, random r/w, 32 thread from guest (debian, kernel 3.16): fio fio1 readtest: (g=0): rw=randrw, bs=4K-4K/4K-4K/4K-4K, ioengine=libaio, iodepth=32 fio-2.1.11 Starting 1 process Jobs: 1 (f=1): [m(1)] [100.0% done] [123.7MB/123.3MB/0KB /s] [31.7K/31.6K/0 iops] [eta 00m:00s] readtest: (groupid=0, jobs=1): err= 0: pid=810: Wed Apr 8 07:26:37 2015 read : io=5117.4MB, bw=148208KB/s, iops=37051, runt= 35357msec slat (usec): min=2, max=2513, avg= 7.27, stdev=10.28 clat (usec): min=104, max=10716, avg=382.30, stdev=113.38 lat (usec): min=108, max=10719, avg=389.94, stdev=115.48 clat percentiles (usec): | 1.00th=[ 215], 5.00th=[ 249], 10.00th=[ 270], 20.00th=[ 298], | 30.00th=[ 318], 40.00th=[ 338], 50.00th=[ 358], 60.00th=[ 386], | 70.00th=[ 418], 80.00th=[ 462], 90.00th=[ 516], 95.00th=[ 572], | 99.00th=[ 756], 99.50th=[ 820], 99.90th=[ 996], 99.95th=[ 1176], | 99.99th=[ 2256] bw (KB /s): min=119296, max=165456, per=99.94%, avg=148124.33, stdev=11834.17 write: io=5114.7MB, bw=148129KB/s, iops=37032, runt= 35357msec slat (usec): min=2, max=2851, avg= 7.55, stdev=10.53 clat (usec): min=172, max=11080, avg=461.92, stdev=137.02 lat (usec): min=178, max=11086, avg=469.86, stdev=138.05 clat percentiles (usec): | 1.00th=[ 278], 5.00th=[ 318], 10.00th=[ 338], 20.00th=[ 366], | 30.00th=[ 390], 40.00th=[ 414], 50.00th=[ 438], 60.00th=[ 466], | 70.00th=[ 494], 80.00th=[ 532], 90.00th=[ 604], 95.00th=[ 716], | 99.00th=[ 900], 99.50th=[ 980], 99.90th=[ 1336], 99.95th=[ 1704], | 99.99th=[ 3408] bw (KB /s): min=119656, max=166680, per=99.93%, avg=148029.21, stdev=11824.30 lat (usec) : 250=2.71%, 500=77.22%, 750=17.60%, 1000=2.21% lat (msec) : 2=0.24%, 4=0.02%, 10=0.01%, 20=0.01% cpu : usr=27.92%, sys=55.44%, ctx=91283, majf=0, minf=7 IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=100.0%, >=64=0.0% submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0% complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.1%, 64=0.0%, >=64=0.0% issued : total=r=1310044/w=1309348/d=0, short=r=0/w=0/d=0 latency : target=0, window=0, percentile=100.00%, depth=32 Run status group 0 (all jobs): READ: io=5117.4MB, aggrb=148207KB/s, minb=148207KB/s, maxb=148207KB/s, mint=35357msec, maxt=35357msec WRITE: io=5114.7MB, aggrb=148128KB/s, minb=148128KB/s, maxb=148128KB/s, mint=35357msec, maxt=35357msec Disk stats (read/write): vdb: ios=1302512/1301780, merge=0/0, ticks=294828/407184, in_queue=701380, util=99.51% In my tests virtio-scsi shows worse results than virtio-blk. Host kernel 3.19-3, qemu-system-x86_64 -version QEMU emulator version 2.0.0. -- WBR Konstantin V. Krotov