On Wed, 2016-12-21 at 16:25 +0100, Martin Sivak wrote: > > So VMs on one host will get better IO performance and the others will > still use NFS as they do now.
Performance is not an issue when all I/O bound VMs are co-located with disks. If all VMs are I/O bound, all hosts in a cluster can use local storage. > 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). Losing a server together with a storage could be an issue, or not. It really depends on setup. At least it would be good to provide such feature :) > 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 <[email protected]> > 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=1 > > > 406412 > > > > > > 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/[email protected]/msg36719.html > > > https://www.mail-archive.com/[email protected]/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 > > [email protected] > > http://lists.ovirt.org/mailman/listinfo/devel > _______________________________________________ > Devel mailing list > [email protected] > http://lists.ovirt.org/mailman/listinfo/devel _______________________________________________ Devel mailing list [email protected] http://lists.ovirt.org/mailman/listinfo/devel
