Hello,
Speaking of rotating-media-under-filestore case(must be most common in Ceph deployments), can peering be less greedy for disk operations without slowing down entire 'blackhole timeout', e.g. when it blocks client operations? I`m suffering of very long and very disk-intensive peering process even on relatively small reweighs on more or less significant commit on the underlying storage(50% are very hard to deal with, 10% of disk commit way more acceptable). Recovery by itself can be throttled low enough to not compete with I/O disk operations from clients but slowing peering process means freezing client` I/O for longer time, that`s all. Cuttlefish seems to do a part of disk controller` job for merging writes, but peering is still unacceptably long for _IOPS_-intensive cluster(5Mb/s and 800 IOPS on every disk during peering, despite controller aligning head movements, disks are 100% busy). SSD-based cluster which should not die under lack of IOPS, but prices for such thing still closer to the TrueEnterpriseStorage(tm) than any solution I can afford. _______________________________________________ ceph-users mailing list [email protected] http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
