[ovirt-users] Ovirt with bad IO performance
Gabriel Ozaki
gabriel.ozaki at kemi.com.br
Tue Sep 6 14:26:51 UTC 2016
Hi Yaniv
This results is averange in sysbench, my machine for example gets
1.3905Mb/sec, i don't know how this test really works and i will search
about it
So i try to make a* bonnie++ test* ( reference
http://support.commgate.net/index.php?/Knowledgebase/Article/View/212 ):
Xenserver speeds:
Write speed: 91076 KB/sec
ReWrite speed: 57885 KB/sec
Read speed: 215457 KB/sec (Strange, too high)
Num of Blocks: 632.4
Ovirt Speeds:
Write speed: 111597 KB/sec (22% more then xenserver)
ReWrite speed: 73402 KB/sec (26% more then xenserver)
Read speed: 121537 KB/sec (44% less then xenserver)
Num of Blocks: 537.2 ( 15% less then xenserver)
result: a draw?
And* DD test *( reference: https://romanrm.net/dd-benchmark )*:*
[root at xenserver teste]# echo 2 > /proc/sys/vm/drop_caches && sync
[root at xenserver teste]# dd bs=1M count=256 if=/dev/zero of=test
conv=fdatasync
256+0 registros de entrada
256+0 registros de saída
268435456 bytes (268 MB) copiados, 1,40111 s, 192 MB/s (Again, too high)
[root at ovirt teste]# echo 2 > /proc/sys/vm/drop_caches && sync
[root at ovirt teste]# dd bs=1M count=256 if=/dev/zero of=test conv=fdatasync
256+0 registros de entrada
256+0 registros de saída
268435456 bytes (268 MB) copiados, 2,31288 s, 116 MB/s (Really fair, the
host result is 124 MB/s)
*HDparm *(FAIL on xenserver)
[root at xenserver teste]# hdparm -Tt /dev/xvda1
/dev/xvda1:
Timing cached reads: 25724 MB in 2.00 seconds = 12882.77 MB/sec
Timing buffered disk reads: 2984 MB in 3.00 seconds = 994.43 MB/sec ( 8
times the expect value, something is very wrong)
[root at ovirt teste]# hdparm -Tt /dev/vda1
/dev/vda1:
Timing cached reads: 25042 MB in 2.00 seconds = 12540.21 MB/sec
Timing buffered disk reads: 306 MB in 3.01 seconds = 101.66 MB/sec(ok
result)
There is something strange in xenserver affecting the results, probably the
best choice is close the thread and start the studies about benchmarks
Thanks
2016-09-05 12:01 GMT-03:00 Yaniv Kaul <ykaul at redhat.com>:
>
>
> On Mon, Sep 5, 2016 at 1:45 PM, Gabriel Ozaki <gabriel.ozaki at kemi.com.br>
> wrote:
>
>> Hi Yaniv and Sandro
>>
>> The disk is in the same machine then ovirt-engine
>>
>
> I'm looking back at your results, and something is terribly wrong there:
> For example, sysbench:
>
> Host result: 2.9843Mb/sec
> Ovirt result: 1.1561Mb/sec
> Xenserver result: 2.9006Mb/sec
>
> This is slower than a USB1 disk on key performance. I don't know what to
> make of it, but it's completely bogus. Even plain QEMU can get better
> results than this.
> And the 2nd benchmark:
>
>
> **The novabench test:*
> Ovirt result: 79Mb/s
> Xenserver result: 101Mb/s
>
> This is better, but still very slow. If I translate it to MB/s, it's
> ~10-12MBs - still very very slow.
> If, however, this is MB/sec, then this makes sense - and is probably as
> much as you can get from a single spindle.
> The difference between XenServer and oVirt are more likely have to do with
> caching than anything else. I don't know what the caching settings of
> XenServer - can you ensure no caching ('direct IO') is used?
>
>
>
>> Thanks
>>
>>
>>
>>
>>
>> 2016-09-02 15:31 GMT-03:00 Yaniv Kaul <ykaul at redhat.com>:
>>
>>>
>>>
>>> On Fri, Sep 2, 2016 at 6:11 PM, Gabriel Ozaki <gabriel.ozaki at kemi.com.br
>>> > wrote:
>>>
>>>> Hi Yaniv
>>>>
>>>> Sorry guys, i don't explain well on my first mail, i notice a bad IO
>>>> performance on *disk* benchmarks, the network are working really fine
>>>>
>>>
>>> But where is the disk? If it's across the network, then network is
>>> involved and is certainly a bottleneck.
>>> Y.
>>>
>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> 2016-09-02 12:04 GMT-03:00 Yaniv Kaul <ykaul at redhat.com>:
>>>>
>>>>> On Fri, Sep 2, 2016 at 5:33 PM, Gabriel Ozaki <
>>>>> gabriel.ozaki at kemi.com.br> wrote:
>>>>>
>>>>>> Hi Nir, thanks for the answer
>>>>>>
>>>>>>
>>>>>> *The nfs server is in the host?*
>>>>>> Yes, i choose NFS to use as storage on ovirt host
>>>>>>
>>>>>> *- Is this 2.9GiB/s or 2.9 MiB/s?*
>>>>>> Is MiB/s, i put the full test on paste bin
>>>>>> centos guest on ovirt:
>>>>>> http://pastebin.com/d48qfvuf
>>>>>>
>>>>>> centos guest on xenserver:
>>>>>> http://pastebin.com/gqN3du29
>>>>>>
>>>>>> how the test works:
>>>>>> https://www.howtoforge.com/how-to-benchmark-your-system-cpu-
>>>>>> file-io-mysql-with-sysbench
>>>>>>
>>>>>> *- Are you testing using NFS in all versions?*
>>>>>> i am using the v3 version
>>>>>>
>>>>>> *- What is the disk format?*
>>>>>> partion size format
>>>>>> / 20Gb xfs
>>>>>> swap 2 Gb xfs
>>>>>> /dados rest of disk xfs (note, this is the partition where i save
>>>>>> the ISOs,exports and VM disks)
>>>>>>
>>>>>>
>>>>>> *- How do you test io on the host?*
>>>>>> I do a clean install of centos and do the test before i install the
>>>>>> ovirt
>>>>>> the test:
>>>>>> http://pastebin.com/7RKU7778
>>>>>>
>>>>>> *- What kind of nic is used? (1G, 10G?)*
>>>>>> Is only a 100mbps :(
>>>>>>
>>>>>
>>>>> 100Mbps will not get you more than several MB/s. 11MB/s on a very
>>>>> bright day...
>>>>>
>>>>>>
>>>>>> *We need much more details to understand what do you test here.*
>>>>>> I have problems to upload the benchmark test on orvirt to novabench
>>>>>> site, so here is the screenshot(i make a mistake on the last email i get
>>>>>> the wrong value), is 86 Mb/s:
>>>>>>
>>>>>
>>>>> Which is not possible on the wire. Unless it's VM to VM? And the
>>>>> storage is local, which means it's the bandwidth of the physical disk
>>>>> itself?
>>>>> Y.
>>>>>
>>>>>
>>>>>
>>>>>>
>>>>>>
>>>>>> And the novabench on xenserver:
>>>>>> https://novabench.com/compare.php?id=ba8dd628e4042dfc1f3d396
>>>>>> 70b164ab11061671
>>>>>>
>>>>>> *- For Xenserver - detailed description of the vm and the storage
>>>>>> configuration?*
>>>>>> The host is the same(i install xenserver, do the tests before i
>>>>>> install centos), the VM i use the same configuration of ovirt, 2 cores, 4
>>>>>> Gb of ram and 60 Gb disk(in the default xenserver SR)
>>>>>>
>>>>>> *- For ovirt, can you share the vm command line, available in
>>>>>> /var/log/libvirt/qemu/vmname.**log?*
>>>>>> 2016-09-01 12:50:28.268+0000: starting up libvirt version: 1.2.17,
>>>>>> package: 13.el7_2.5 (CentOS BuildSystem <http://bugs.centos.org>,
>>>>>> 2016-06-23-14:23:27, worker1.bsys.centos.org), qemu version: 2.3.0
>>>>>> (qemu-kvm-ev-2.3.0-31.el7.16.1)
>>>>>> LC_ALL=C PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin
>>>>>> QEMU_AUDIO_DRV=none /usr/libexec/qemu-kvm -name vmcentos -S -machine
>>>>>> pc-i440fx-rhel7.2.0,accel=kvm,usb=off -cpu Haswell-noTSX -m
>>>>>> size=4194304k,slots=16,maxmem=4294967296k -realtime mlock=off -smp
>>>>>> 2,maxcpus=16,sockets=16,cores=1,threads=1 -numa
>>>>>> node,nodeid=0,cpus=0-1,mem=4096 -uuid 21872e4b-7699-4502-b1ef-2c058eff1c3c
>>>>>> -smbios type=1,manufacturer=oVirt,product=oVirt
>>>>>> Node,version=7-2.1511.el7.centos.2.10,serial=03AA02FC-0414-0
>>>>>> 5F8-D906-710700080009,uuid=21872e4b-7699-4502-b1ef-2c058eff1c3c
>>>>>> -no-user-config -nodefaults -chardev socket,id=charmonitor,path=/va
>>>>>> r/lib/libvirt/qemu/domain-vmcentos/monitor.sock,server,nowait -mon
>>>>>> chardev=charmonitor,id=monitor,mode=control -rtc
>>>>>> base=2016-09-01T09:50:28,driftfix=slew -global
>>>>>> kvm-pit.lost_tick_policy=discard -no-hpet -no-shutdown -boot
>>>>>> strict=on -device piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2
>>>>>> -device virtio-scsi-pci,id=scsi0,bus=pci.0,addr=0x3 -device
>>>>>> virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x4
>>>>>> -drive file=/rhev/data-center/mnt/ovirt.kemi.intranet:_dados_iso/52
>>>>>> ee9f87-9d38-48ec-8003-193262f81994/images/11111111-1111-1111
>>>>>> -1111-111111111111/CentOS-7-x86_64-NetInstall-1511.iso,if=no
>>>>>> ne,id=drive-ide0-1-0,readonly=on,format=raw -device
>>>>>> ide-cd,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0,bootindex=2
>>>>>> -drive file=/rhev/data-center/00000001-0001-0001-0001-0000000002bb/
>>>>>> 4ccdd1f3-ee79-4425-b6ed-5774643003fa/images/2ecfcf18-ae84-4e
>>>>>> 73-922f-28b9cda9e6e1/800f05bf-23f7-4c9d-8c1d-b2503592875f,if
>>>>>> =none,id=drive-virtio-disk0,format=raw,serial=2ecfcf18-ae84-
>>>>>> 4e73-922f-28b9cda9e6e1,cache=none,werror=stop,rerror=stop,aio=threads
>>>>>> -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x6,drive=drive-virti
>>>>>> o-disk0,id=virtio-disk0,bootindex=1 -chardev
>>>>>> socket,id=charchannel0,path=/var/lib/libvirt/qemu/channels/2
>>>>>> 1872e4b-7699-4502-b1ef-2c058eff1c3c.com.redhat.rhevm.vdsm,server,nowait
>>>>>> -device virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel
>>>>>> 0,id=channel0,name=com.redhat.rhevm.vdsm -chardev
>>>>>> socket,id=charchannel1,path=/var/lib/libvirt/qemu/channels/2
>>>>>> 1872e4b-7699-4502-b1ef-2c058eff1c3c.org.qemu.guest_agent.0,server,nowait
>>>>>> -device virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel
>>>>>> 1,id=channel1,name=org.qemu.guest_agent.0 -device
>>>>>> usb-tablet,id=input0 -vnc 192.168.0.189:0,password -k pt-br -device
>>>>>> VGA,id=video0,vgamem_mb=16,bus=pci.0,addr=0x2 -device
>>>>>> virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x5 -msg timestamp=on
>>>>>> 2016-09-01T12:50:28.307173Z qemu-kvm: warning: CPU(s) not present in
>>>>>> any NUMA nodes: 2 3 4 5 6 7 8 9 10 11 12 13 14 15
>>>>>> 2016-09-01T12:50:28.307371Z qemu-kvm: warning: All CPU(s) up to
>>>>>> maxcpus should be described in NUMA config
>>>>>> qemu: terminating on signal 15 from pid 1
>>>>>> 2016-09-01 19:13:47.899+0000: shutting down
>>>>>>
>>>>>>
>>>>>> Thanks
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> 2016-09-02 11:05 GMT-03:00 Nir Soffer <nsoffer at redhat.com>:
>>>>>>
>>>>>>> On Fri, Sep 2, 2016 at 4:44 PM, Gabriel Ozaki <
>>>>>>> gabriel.ozaki at kemi.com.br> wrote:
>>>>>>>
>>>>>>>> Hi
>>>>>>>> i am trying Ovirt 4.0 and i am getting some strange results when
>>>>>>>> comparing with Xenserver
>>>>>>>>
>>>>>>>> **The host machine*
>>>>>>>> Intel Core i5-4440 3.10GHz running at 3093 MHz
>>>>>>>> 8 Gb of RAM (1x8)
>>>>>>>> 500 Gb of Disk (seagate st500dm002 7200rpm)
>>>>>>>> CentOS 7 (netinstall for the most updated and stable packages)
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> **How i am testing:*
>>>>>>>> I choose two benchmark tools, sysbench(epel-repo on centos) and
>>>>>>>> novabench(for windows guest, https://novabench.com ), then i make
>>>>>>>> a clean install of xenserver and create two guests(CentOS and Windows 7 SP1)
>>>>>>>>
>>>>>>>>
>>>>>>>> **The Guest specs*
>>>>>>>> 2 cores
>>>>>>>> 4 Gb of RAM
>>>>>>>> 60 Gb of disk (using virtIO in a NFS storage)
>>>>>>>>
>>>>>>>
>>>>>>> The nfs server is in the host?
>>>>>>>
>>>>>>>
>>>>>>>> Important note: only the testing guest are up on benchmark and i
>>>>>>>> have installed the drivers in guest
>>>>>>>>
>>>>>>>>
>>>>>>>> **The Sysbench disk test(creates 10Gb of data and do the bench):*
>>>>>>>> # sysbench --test=fileio --file-total-size=10G prepare
>>>>>>>> # sysbench --test=fileio --file-total-size=10G
>>>>>>>> --file-test-mode=rndrw --init-rng=on --max-time=300 --max-requests=0 run
>>>>>>>>
>>>>>>>> Host result: 2.9843Mb/sec
>>>>>>>> Ovirt result: 1.1561Mb/sec
>>>>>>>> Xenserver result: 2.9006Mb/sec
>>>>>>>>
>>>>>>>
>>>>>>> - Is this 2.9GiB/s or 2.9 MiB/s?
>>>>>>> - Are you testing using NFS in all versions?
>>>>>>> - What is the disk format?
>>>>>>> - How do you test io on the host?
>>>>>>> - What kind of nic is used? (1G, 10G?)
>>>>>>>
>>>>>>>
>>>>>>>>
>>>>>>>> **The novabench test:*
>>>>>>>> Ovirt result: 79Mb/s
>>>>>>>> Xenserver result: 101Mb/s
>>>>>>>>
>>>>>>>
>>>>>>> We need much more details to understand what do you test here.
>>>>>>>
>>>>>>> - For ovirt, can you share the vm command line, available in
>>>>>>> /var/log/libvirt/qemu/vmname.log?
>>>>>>> - For Xenserver - detailed description of the vm and the storage
>>>>>>> configuration?
>>>>>>>
>>>>>>> Nir
>>>>>>>
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> Users mailing list
>>>>>> Users at ovirt.org
>>>>>> http://lists.ovirt.org/mailman/listinfo/users
>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.ovirt.org/pipermail/users/attachments/20160906/6ea5a2ed/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ovirt-sem-driver.png
Type: image/png
Size: 29812 bytes
Desc: not available
URL: <http://lists.ovirt.org/pipermail/users/attachments/20160906/6ea5a2ed/attachment-0001.png>
More information about the Users
mailing list