Re: [ovirt-users] Ovirt with bad IO performance

On Mon, Sep 5, 2016 at 1:45 PM, Gabriel Ozaki <gabriel.ozaki(a)kemi.com.br&gt; 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(a)redhat.com&gt;: > >> >> >> On Fri, Sep 2, 2016 at 6:11 PM, Gabriel Ozaki <gabriel.ozaki(a)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(a)redhat.com&gt;: >>> >>>> On Fri, Sep 2, 2016 at 5:33 PM, Gabriel Ozaki < >>>> gabriel.ozaki(a)kemi.com.br&gt; 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(a)redhat.com&gt;: >>>>> >>>>>> On Fri, Sep 2, 2016 at 4:44 PM, Gabriel Ozaki < >>>>>> gabriel.ozaki(a)kemi.com.br&gt; 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(a)ovirt.org >>>>> http://lists.ovirt.org/mailman/listinfo/users >>>>> >>>>> >>>> >>> >> >