On Wed, Jun 15, 2011 at 6:10 PM, Pekka Enberg <penberg@xxxxxxxxxx> wrote: > On Wed, Jun 15, 2011 at 7:30 PM, Avi Kivity <avi@xxxxxxxxxx> wrote: >> On 06/15/2011 06:53 PM, Pekka Enberg wrote: >>> >>> - Fast QCOW2 image read-write support beating Qemu in fio benchmarks. See >>> the >>> following URL for test result details: https://gist.github.com/1026888 >> >> This is surprising. How is qemu invoked? > > Prasad will have the details. Please note that the above are with Qemu > defaults which doesn't use virtio. The results with virtio are little > better but still in favor of tools/kvm. > The qcow2 image used for testing was copied on to /dev/shm to avoid the disk delays in performance measurement. QEMU was invoked with following parameters $ qemu-system-x86_64 -hda <disk image on hard disk> -hdb /dev/shm/test.qcow2 -m 1024M FIO job file used for measuring the numbers was prasad@prasad-vm:~$ cat fio-mixed.job ; fio-mixed.job for autotest [global] name=fio-sync directory=/mnt rw=randrw rwmixread=67 rwmixwrite=33 bsrange=16K-256K direct=0 end_fsync=1 verify=crc32 ;ioscheduler=x numjobs=4 [file1] size=50M ioengine=sync mem=malloc [file2] stonewall size=50M ioengine=aio mem=shm iodepth=4 [file3] stonewall size=50M ioengine=mmap mem=mmap direct=1 [file4] stonewall size=50M ioengine=splice mem=malloc direct=1 - The test generates 16 file each of ~50MB, so in total ~800MB data was written. - The test.qcow2 was newly created before it was used with QEMU or KVM tool - The size of the QCOW2 image was 1.5GB. - The host machine had 2GB RAM. - The guest machine in both the cases was started with 1GB memory. Thanks and Regards, Prasad >> btw the dump above is a little hard to interpret. > > It's what fio reports. The relevant bits are: > > > Qemu: > > Run status group 0 (all jobs): > READ: io=204800KB, aggrb=61152KB/s, minb=15655KB/s, maxb=17845KB/s, > mint=2938msec, maxt=3349msec > WRITE: io=68544KB, aggrb=28045KB/s, minb=6831KB/s, maxb=7858KB/s, > mint=2292msec, maxt=2444msec > > Run status group 1 (all jobs): > READ: io=204800KB, aggrb=61779KB/s, minb=15815KB/s, maxb=17189KB/s, > mint=3050msec, maxt=3315msec > WRITE: io=66576KB, aggrb=24165KB/s, minb=6205KB/s, maxb=7166KB/s, > mint=2485msec, maxt=2755msec > > Run status group 2 (all jobs): > READ: io=204800KB, aggrb=6722KB/s, minb=1720KB/s, maxb=1737KB/s, > mint=30178msec, maxt=30467msec > WRITE: io=65424KB, aggrb=2156KB/s, minb=550KB/s, maxb=573KB/s, > mint=29682msec, maxt=30342msec > > Run status group 3 (all jobs): > READ: io=204800KB, aggrb=6994KB/s, minb=1790KB/s, maxb=1834KB/s, > mint=28574msec, maxt=29279msec > WRITE: io=68192KB, aggrb=2382KB/s, minb=548KB/s, maxb=740KB/s, > mint=27121msec, maxt=28625msec > > Disk stats (read/write): > sdb: ios=60583/6652, merge=0/164, ticks=156340/672030, > in_queue=828230, util=82.71% > > tools/kvm: > > Run status group 0 (all jobs): > READ: io=204800KB, aggrb=149162KB/s, minb=38185KB/s, > maxb=46030KB/s, mint=1139msec, maxt=1373msec > WRITE: io=70528KB, aggrb=79156KB/s, minb=18903KB/s, maxb=23726KB/s, > mint=804msec, maxt=891msec > > Run status group 1 (all jobs): > READ: io=204800KB, aggrb=188235KB/s, minb=48188KB/s, > maxb=57932KB/s, mint=905msec, maxt=1088msec > WRITE: io=64464KB, aggrb=84821KB/s, minb=21751KB/s, maxb=27392KB/s, > mint=570msec, maxt=760msec > > Run status group 2 (all jobs): > READ: io=204800KB, aggrb=20005KB/s, minb=5121KB/s, maxb=5333KB/s, > mint=9830msec, maxt=10237msec > WRITE: io=66624KB, aggrb=6615KB/s, minb=1671KB/s, maxb=1781KB/s, > mint=9558msec, maxt=10071msec > > Run status group 3 (all jobs): > READ: io=204800KB, aggrb=66149KB/s, minb=16934KB/s, maxb=17936KB/s, > mint=2923msec, maxt=3096msec > WRITE: io=69600KB, aggrb=26717KB/s, minb=6595KB/s, maxb=7342KB/s, > mint=2530msec, maxt=2605msec > > Disk stats (read/write): > vdb: ios=61002/6654, merge=0/183, ticks=27270/205780, > in_queue=232220, util=69.46% > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
