Re: [Users] Extremely poor disk access speeds in Windows guest

Adding the virtio-scsi developers. Anyhow, virtio-scsi is newer and less established than viostor (the block device), so you might want to try it out.

A disclaimer: There are time and patches gaps between RHEL and other versions. Ronen. On 01/28/2014 10:39 PM, Steve Dainard wrote: > I've had a bit of luck here. > > > Overall IO performance is very poor during Windows updates, but a > contributing factor seems to be the "SCSI Controller" device in the > guest. This last install I didn't install a driver for that device,

> and my performance is much better. Updates still chug along quite > slowly, but I seem to have more than the < 100KB/s write speeds I > was seeing previously. > > > Does anyone know what this device is for? I have the "Red Hat VirtIO > SCSI Controller" listed under storage controllers.

> > Steve Dainard > IT Infrastructure Manager > Miovision | Rethink Traffic > 519-513-2407 ex.250 > 877-646-8476 (toll-free) > > Blog | LinkedIn | Twitter | Facebook > ____________________________________________________________________ > Miovision Technologies Inc. | 148 Manitou Drive, Suite 101, > Kitchener, ON, Canada | N2C 1L3 > This e-mail may contain information that is privileged or > confidential. If you are not the intended recipient, please delete > the e-mail and any attachments and notify us immediately. > > > On Sun, Jan 26, 2014 at 2:33 AM, Itamar Heim <iheim(a)redhat.com&gt; > wrote: > On 01/26/2014 02:37 AM, Steve Dainard wrote: > > Thanks for the responses everyone, really appreciate > it. > > I've condensed the other questions into this reply. > > > Steve, > What is the CPU load of the GlusterFS host when > comparing the raw > brick test to the gluster mount point test? Give > it 30 seconds and > see what top reports. You’ll probably have to > significantly increase > the count on the test so that it runs that long. > > - Nick > > > > Gluster mount point: > > *4K* on GLUSTER host > [root@gluster1 rep2]# dd if=/dev/zero > of=/mnt/rep2/test1 bs=4k count=500000 > 500000+0 records in > 500000+0 records out > > 2048000000 <tel:2048000000> bytes (2.0 GB) copied, > 100.076 s, 20.5 MB/s > > > Top reported this right away: > PID USER PR NI VIRT RES SHR S %CPU %MEM > TIME+ COMMAND > 1826 root 20 0 294m 33m 2540 S 27.2 0.4 > 0:04.31 glusterfs > 2126 root 20 0 1391m 31m 2336 S 22.6 0.4 > 11:25.48 glusterfsd > > Then at about 20+ seconds top reports this: > PID USER PR NI VIRT RES SHR S %CPU %MEM > TIME+ COMMAND > 1826 root 20 0 294m 35m 2660 R 141.7 0.5 > 1:14.94 glusterfs > 2126 root 20 0 1392m 31m 2344 S 33.7 0.4 > 11:46.56 glusterfsd > > *4K* Directly on the brick: > dd if=/dev/zero of=test1 bs=4k count=500000 > 500000+0 records in > 500000+0 records out > > 2048000000 <tel:2048000000> bytes (2.0 GB) copied, > 4.99367 s, 410 MB/s > > > 7750 root 20 0 102m 648 544 R 50.3 0.0 > 0:01.52 dd > 7719 root 20 0 0 0 0 D 1.0 0.0 > 0:01.50 flush-253:2 > > Same test, gluster mount point on OVIRT host: > dd if=/dev/zero of=/mnt/rep2/test1 bs=4k > count=500000 > 500000+0 records in > 500000+0 records out > > 2048000000 <tel:2048000000> bytes (2.0 GB) copied, > 42.4518 s, 48.2 MB/s > > > PID USER PR NI VIRT RES SHR S %CPU %MEM > TIME+ COMMAND > 2126 root 20 0 1396m 31m 2360 S 40.5 0.4 > 13:28.89 glusterfsd > > > Same test, on OVIRT host but against NFS mount > point: > dd if=/dev/zero of=/mnt/rep2-nfs/test1 bs=4k > count=500000 > 500000+0 records in > 500000+0 records out > > 2048000000 <tel:2048000000> bytes (2.0 GB) copied, > 18.8911 s, 108 MB/s > > > PID USER PR NI VIRT RES SHR S %CPU %MEM > TIME+ COMMAND > 2141 root 20 0 550m 184m 2840 R 84.6 2.3 > 16:43.10 glusterfs > 2126 root 20 0 1407m 30m 2368 S 49.8 0.4 > 13:49.07 glusterfsd > > Interesting - It looks like if I use a NFS mount > point, I incur a cpu > hit on two processes instead of just the daemon. I > also get much better > performance if I'm not running dd (fuse) on the > GLUSTER host. > > > The storage servers are a bit older, but are > both dual socket > quad core > > opterons with 4x 7200rpm drives. > > > A block size of 4k is quite small so that the > context switch > overhead involved with fuse would be more > perceivable. > > Would it be possible to increase the block size > for dd and test? > > > > I'm in the process of setting up a share > from my desktop and > I'll see if > > I can bench between the two systems. Not > sure if my ssd will > impact the > > tests, I've heard there isn't an advantage > using ssd storage for > glusterfs. > > > Do you have any pointers to this source of > information? Typically > glusterfs performance for virtualization work > loads is bound by the > slowest element in the entire stack. Usually > storage/disks happen to > be the bottleneck and ssd storage does benefit > glusterfs. > > -Vijay > > > I had a couple technical calls with RH (re: RHSS), > and when I asked if > SSD's could add any benefit I was told no. The > context may have been in > a product comparison to other storage vendors, where > they use SSD's for > read/write caching, versus having an all SSD storage > domain (which I'm > not proposing, but which is effectively what my > desktop would provide). > > Increasing bs against NFS mount point (gluster > backend): > dd if=/dev/zero of=/mnt/rep2-nfs/test1 bs=128k > count=16000 > 16000+0 records in > 16000+0 records out > > 2097152000 <tel:2097152000> bytes (2.1 GB) copied, > 19.1089 s, 110 MB/s > > > > GLUSTER host top reports: > PID USER PR NI VIRT RES SHR S %CPU %MEM > TIME+ COMMAND > 2141 root 20 0 550m 183m 2844 R 88.9 2.3 > 17:30.82 glusterfs > 2126 root 20 0 1414m 31m 2408 S 46.1 0.4 > 14:18.18 glusterfsd > > So roughly the same performance as 4k writes > remotely. I'm guessing if I > could randomize these writes we'd see a large > difference. > > > Check this thread out, > > http://raobharata.wordpress.com/2012/10/29/qemu-glusterfs-native-integrat... it's > quite dated but I remember seeing similar > figures. > > In fact when I used FIO on a libgfapi mounted VM > I got slightly > faster read/write speeds than on the physical > box itself (I assume > because of some level of caching). On NFS it was > close to half.. > You'll probably get a little more interesting > results using FIO > opposed to dd > > ( -Andrew) > > > Sorry Andrew, I meant to reply to your other message > - it looks like > CentOS 6.5 can't use libgfapi right now, I stumbled > across this info in > a couple threads. Something about how the CentOS > build has different > flags set on build for RHEV snapshot support then > RHEL, so native > gluster storage domains are disabled because > snapshot support is assumed > and would break otherwise. I'm assuming this is > still valid as I cannot > get a storage lock when I attempt a gluster storage > domain. > > > -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- > > I've setup a NFS storage domain on my desktops SSD. > I've re-installed > win 2008 r2 and initially it was running smoother. > > Disk performance peaks at 100MB/s. > > If I copy a 250MB file from a share into the Windows > VM, it writes out

> quickly, less than 5 seconds. > > If I copy 20 files, ranging in file sizes from 4k to > 200MB, totaling in > 650MB from the share - windows becomes unresponsive, > in top the > desktop's nfs daemon is barely being touched at all, > and then eventually > is not hit. I can still interact with the VM's > windows through the spice > console. Eventually the file transfer will start and > rocket through the > transfer. > > I've opened a 271MB zip file with 4454 files and > started the extract > process but the progress windows will sit on > 'calculating...' after a > significant period of time the decompression starts > and runs at > <200KB/second. Windows is guesstimating 1HR > completion time. Eventually > even this freezes up, and my spice console mouse > won't grab. I can still > see the resource monitor in the Windows VM doing its > thing but have to > poweroff the VM as its no longer usable. > > The windows update process is the same. It seems > like when the guest > needs quick large writes its fine, but lots of io > causes serious > hanging, unresponsiveness, spice mouse cursor > freeze, and eventually > poweroff/reboot is the only way to get it back. > > Also, during window 2008 r2 install the 'expanding > windows files' task > is quite slow, roughly 1% progress every 20 seconds > (~30 mins to > complete). The GLUSTER host shows these stats pretty > consistently: > PID USER PR NI VIRT RES SHR S %CPU %MEM > TIME+ COMMAND > 8139 root 20 0 1380m 28m 2476 R 83.1 0.4 > 8:35.78 glusterfsd > 8295 root 20 0 550m 186m 2980 S 4.3 2.4 > 1:52.56 glusterfs > > bwm-ng v0.6 (probing every 2.000s), press 'h' for > help > input: /proc/net/dev type: rate > \ iface Rx > Tx > Total > > ============================================================================== > lo: 3719.31 KB/s > 3719.31 KB/s > 7438.62 KB/s > eth0: 3405.12 KB/s > 3903.28 KB/s > 7308.40 KB/s > > > I've copied the same zip file to an nfs mount point > on the OVIRT host > (gluster backend) and get about 25 - 600 KB/s during > unzip. The same > test on NFS mount point (desktop SSD ext4 backend) > averaged a network > transfer speed of 5MB/s and completed in about 40 > seconds. > > I have a RHEL 6.5 guest running on the NFS/gluster > backend storage > domain, and just did the same test. Extracting the > file took 22.3 > seconds (faster than the fuse mount point on the > host !?!?). > > GLUSTER host top reported this while the RHEL guest > was decompressing > the zip file: > PID USER PR NI VIRT RES SHR S %CPU %MEM > TIME+ COMMAND > 2141 root 20 0 555m 187m 2844 S 4.0 2.4 > 18:17.00 glusterfs > 2122 root 20 0 1380m 31m 2396 S 2.3 0.4 > 83:19.40 glusterfsd > > > > > > > *Steve Dainard * > IT Infrastructure Manager > Miovision <http://miovision.com/> | /Rethink > Traffic/ > 519-513-2407 <tel:519-513-2407> ex.250 > 877-646-8476 <tel:877-646-8476> (toll-free) > > *Blog <http://miovision.com/blog> | **LinkedIn > <https://www.linkedin.com/company/miovision-technologies> | Twitter > <https://twitter.com/miovision> | Facebook > <https://www.facebook.com/miovision>* > ------------------------------------------------------------------------ > > Miovision Technologies Inc. | 148 Manitou Drive, > Suite 101, Kitchener, > ON, Canada | N2C 1L3 > This e-mail may contain information that is > privileged or confidential. > If you are not the intended recipient, please delete > the e-mail and any > attachments and notify us immediately. > > > > > > _______________________________________________ > Users mailing list > Users(a)ovirt.org > http://lists.ovirt.org/mailman/listinfo/users > > > > please note currently (>3.3.1), we don't use libgfapi on > fedora as well, as we found some gaps in functionality in > the libvirt libgfapi support for snapshots. once these are > resolved, we can re-enable libgfapi on a glusterfs storage > domain. > >