On Sun, Feb 8, 2015 at 6:00 PM, Sumit Gaur <sumitkg...@gmail.com> wrote: > Hi > I have installed 6 node ceph cluster and doing a performance bench mark for > the same using Nova VMs. What I have observed that FIO random write reports > around 250 MBps for 1M block size and PGs 4096 and 650MBps for iM block size > and PG counts 2048 . Can some body let me know if I am missing any ceph > Architecture point here ? As per my understanding PG numbers are mainly > involved in calculating the hash and should not effect performance so much.
PGs are also serialization points within the codebase, so depending on how you're testing you can run into contention if you have multiple objects within a single PG that you're trying to write to at once. This isn't normally a problem, but for a single benchmark run the random collisions can become noticeable. -Greg _______________________________________________ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
