Re: [ovirt-devel] [RFE] treat local NFS storage as localfs

On 21 Dec 2016, at 16:26, Martin Sivak <msivak(a)redhat.com&gt; wrote: Hi, > Hope this get's in. This seems less overhead than a complete > hyperconverged gluster setup. But NFS still is a single point of failure. Hyperconverged is supposed to address that. >> In order to improve performance, disk I/O bound VMs can be pinned to >> a host with local storage. However there still is a performance >> drawback of NFS layers. Treating a local NFS storage as a local storage >> improves performance for VMs pinned to host. So VMs on one host will get better IO performance and the others will still use NFS as they do now. It is an interesting idea, I am just not sure if having poor-man's hyperconverged setup with all the drawbacks of NFS is worth it. Imagine for example what happens when that storage provider host needs to be fenced or put into maintenance. The whole cluster would go down (all VMs would lose storage connection, not just the VMs from the affected host). I will let someone from the storage team to respond to this, but I do not think that trading performance (each host has its own local storage) and resilience (well, at least one failing host does not affect the others) for migrations is a good deal.

-- Martin Sivak SLA / oVirt > On Wed, Dec 21, 2016 at 2:18 PM, Sven Kieske <s.kieske(a)mittwald.de&gt; wrote: >> On 21/12/16 11:44, Pavel Gashev wrote: >> Hello, >> >> I'd like to introduce a RFE that allows to use a local storage in multi >> server environments https://bugzilla.redhat.com/show_bug.cgi?id=1406412 >> >> Most servers have a local storage. Some servers have very reliable >> storages with hardware RAID controllers and battery units. >> >> Example user cases: >> https://www.mail-archive.com/users@ovirt.org/msg36719.html >> https://www.mail-archive.com/users@ovirt.org/msg36772.html >> >> The best way to use local storage in multi server "shared" datacenters >> is exporting it over NFS. Using NFS allows to move disks and VMs among >> servers. >> >> In order to improve performance, disk I/O bound VMs can be pinned to >> a host with local storage. However there still is a performance >> drawback of NFS layers. Treating a local NFS storage as a local storage >> improves performance for VMs pinned to host. >> >> Currently setting up of NFS exports is out of scope of oVirt. However >> this would be a way to get rid of "Local/Shared" storage types of >> datacenter. So that all storages are shared, but local storages are >> used as local. >> >> Any questions/comments are welcome. >> >> Specifically I'd like to request for comment on potential data >> integrity issues during online VM or disk migration between NFS and >> localfs. >> > > Just let me say that I really like this as an end user. > > Hope this get's in. This seems less overhead than a complete > hyperconverged gluster setup. > > > -- > Mit freundlichen Grüßen / Regards > > Sven Kieske > > Systemadministrator > Mittwald CM Service GmbH & Co. KG > Königsberger Straße 6 > 32339 Espelkamp > T: +495772 293100 > F: +495772 293333 > https://www.mittwald.de > Geschäftsführer: Robert Meyer > St.Nr.: 331/5721/1033, USt-IdNr.: DE814773217, HRA 6640, AG Bad Oeynhausen > Komplementärin: Robert Meyer Verwaltungs GmbH, HRB 13260, AG Bad Oeynhausen > > > _______________________________________________ > Devel mailing list > Devel(a)ovirt.org > http://lists.ovirt.org/mailman/listinfo/devel _______________________________________________ Devel mailing list Devel(a)ovirt.org http://lists.ovirt.org/mailman/listinfo/devel