Re: [ovirt-users] [Gluster-users] slow performance with export storage on glusterfs

What about mounting over nfs instead of the fuse client. Or maybe libgfapi. Is that available for export domains On Fri, Nov 24, 2017 at 3:48 AM Jiří Sléžka <jiri.slezka(a)slu.cz&gt; wrote: > On 11/24/2017 06:41 AM, Sahina Bose wrote: > > > > > > On Thu, Nov 23, 2017 at 4:56 PM, Jiří Sléžka <jiri.slezka(a)slu.cz > > <mailto:jiri.slezka@slu.cz>> wrote: > > > > Hi, > > > > On 11/22/2017 07:30 PM, Nir Soffer wrote: > > > On Mon, Nov 20, 2017 at 5:22 PM Jiří Sléžka <jiri.slezka(a)slu.cz > <mailto:jiri.slezka@slu.cz> > > > <mailto:jiri.slezka@slu.cz <mailto:jiri.slezka@slu.cz>>> wrote: > > > > > > Hi, > > > > > > I am trying realize why is exporting of vm to export storage > on > > > glusterfs such slow. > > > > > > I am using oVirt and RHV, both instalations on version 4.1.7. > > > > > > Hosts have dedicated nics for rhevm network - 1gbps, data > > storage itself > > > is on FC. > > > > > > GlusterFS cluster lives separate on 4 dedicated hosts. It has > > slow disks > > > but I can achieve about 200-400mbit throughput in other > > applications (we > > > are using it for "cold" data, backups mostly). > > > > > > I am using this glusterfs cluster as backend for export > > storage. When I > > > am exporting vm I can see only about 60-80mbit throughput. > > > > > > What could be the bottleneck here? > > > > > > Could it be qemu-img utility? > > > > > > vdsm 97739 0.3 0.0 354212 29148 ? S<l 15:43 > 0:06 > > > /usr/bin/qemu-img convert -p -t none -T none -f raw > > > > > /rhev/data-center/2ff6d0ee-a10b-473d-b77c-be9149945f5f/ > ff3cd56a-1005-4426-8137-8f422c0b47c1/images/ba42cbcc- > c068-4df8-af3d-00f2077b1e27/c57acd5f-d6cf-48cc-ad0c-4a7d979c0c1e > > > -O raw > > > > > /rhev/data-center/mnt/glusterSD/10.20.30.41:_rhv__ > export/81094499-a392-4ea2-b081-7c6288fbb636/images/ > ba42cbcc-c068-4df8-af3d-00f2077b1e27/c57acd5f-d6cf-48cc-ad0c-4a7d979c0c1e > > > > > > Any idea how to make it work faster or what throughput should > I > > > expected? > > > > > > > > > gluster storage operations are using fuse mount - so every write: > > > - travel to the kernel > > > - travel back to the gluster fuse helper process > > > - travel to all 3 replicas - replication is done on client side > > > - return to kernel when all writes succeeded > > > - return to caller > > > > > > So gluster will never set any speed record. > > > > > > Additionally, you are copying from raw lv on FC - qemu-img cannot > do > > > anything > > > smart and avoid copying unused clusters. Instead if copies > > gigabytes of > > > zeros > > > from FC. > > > > ok, it does make sense > > > > > However 7.5-10 MiB/s sounds too slow. > > > > > > I would try to test with dd - how much time it takes to copy > > > the same image from FC to your gluster storage? > > > > > > dd > > > if=/rhev/data-center/2ff6d0ee-a10b-473d-b77c-be9149945f5f/ > ff3cd56a-1005-4426-8137-8f422c0b47c1/images/ba42cbcc- > c068-4df8-af3d-00f2077b1e27/c57acd5f-d6cf-48cc-ad0c-4a7d979c0c1e > > > of=/rhev/data-center/mnt/glusterSD/10.20.30.41:_rhv__ > export/81094499-a392-4ea2-b081-7c6288fbb636/__test__ > > > bs=8M oflag=direct status=progress > > > > unfrotunately dd performs the same > > > > 1778384896 bytes (1.8 GB) copied, 198.565265 s, 9.0 MB/s > > > > > > > If dd can do this faster, please ask on qemu-discuss mailing list: > > > https://lists.nongnu.org/mailman/listinfo/qemu-discuss > > <https://lists.nongnu.org/mailman/listinfo/qemu-discuss> > > > > > > If both give similar results, I think asking in gluster mailing > list > > > about this can help. Maybe your gluster setup can be optimized. > > > > ok, this is definitly on the gluster side. Thanks for your guidance. > > > > I will investigate the gluster side and also will try Export on NFS > > share. > > > > > > [Adding gluster users ml] > > > > Please provide "gluster volume info" output for the rhv_export gluster > > volume and also volume profile details (refer to earlier mail from Shani > > on how to run this) while performing the dd operation above. > > you can find all this output on https://pastebin.com/sBK01VS8 > > as mentioned in other posts. Gluster cluster uses really slow (green) > disks but without direct io it can achieve throughput around 400mbit/s. > > This storage is used mostly for backup purposes. It is not used as a vm > storage. > > In my case it would be nice not to use direct io in export case but I > understand why it might not be wise. > > Cheers, > > Jiri > > > > > > > > > > > Cheers, > > > > Jiri > > > > > > > > > > Nir > > > > > > > > > > > > Cheers, > > > > > > Jiri > > > > > > > > > _______________________________________________ > > > Users mailing list > > > Users(a)ovirt.org <mailto:Users@ovirt.org> > > <mailto:Users@ovirt.org <mailto:Users@ovirt.org>> > > > http://lists.ovirt.org/mailman/listinfo/users > > <http://lists.ovirt.org/mailman/listinfo/users> > > > > > > > > > > > _______________________________________________ > > Users mailing list > > Users(a)ovirt.org <mailto:Users@ovirt.org> > > http://lists.ovirt.org/mailman/listinfo/users > > <http://lists.ovirt.org/mailman/listinfo/users> > > > > > > > _______________________________________________ > Users mailing list > Users(a)ovirt.org > http://lists.ovirt.org/mailman/listinfo/users > _______________________________________________ Gluster-users mailing list Gluster-users(a)gluster.org http://lists.gluster.org/mailman/listinfo/gluster-users