+1 .. I agree.... Thanks Swami On Tue, Jul 19, 2016 at 4:57 PM, Lionel Bouton <lionel+ceph@xxxxxxxxxxx> wrote: > Hi, > > On 19/07/2016 13:06, Wido den Hollander wrote: >>> Op 19 juli 2016 om 12:37 schreef M Ranga Swami Reddy <swamireddy@xxxxxxxxx>: >>> >>> >>> Thanks for the correction...so even one OSD reaches to 95% full, the >>> total ceph cluster IO (R/W) will be blocked...Ideally read IO should >>> work... >> That should be a config option, since reading while writes still block is also a danger. Multiple clients could read the same object, perform a in-memory change and their write will block. >> >> Now, which client will 'win' after the full flag has been removed? >> >> That could lead to data corruption. > > If it did, the clients would be broken as normal usage (without writes > being blocked) doesn't prevent multiple clients from reading the same > data and trying to write at the same time. So if multiple writes (I > suppose on the same data blocks) are possibly waiting the order in which > they are performed *must not* matter in your system. The alternative is > to prevent simultaneous write accesses from multiple clients (this is > how non-cluster filesystems must be configured on top of Ceph/RBD, they > must even be prevented from read-only accessing an already mounted fs). > >> >> Just make sure you have proper monitoring on your Ceph cluster. At nearfull it goes into WARN and you should act on that. > > > +1 : monitoring is not an option. > > Lionel _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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