On Wed, Mar 8, 2017 at 7:54 PM, Rhian Resnick <rresnick at fau.edu> wrote: > Two questions on Cephfs and erasure coding that Google couldn't answer. > > > > 1) How well does cephfs work with erasure coding? > In the current released versions, you cannot use erasure coded pools with CephFS, unless there is a replicated cache tier in between. This isn't generally advisable because cache tiers bring their own complexity. The reason for all this is that currently, erasure coded pools only support a subset of operations. Notably they do not support overwriting objects (i.e. modifying in place, the way we would in a filesystem when someone writes to an existing file). There is work underway to remove that limitation. In the current master (development) code it is already possible to use erasure coded pools directly as cephfs data pools when a special setting is used to enable overwrites in EC pools. John > > 2) How would you move an existing cephfs pool that uses replication to > erasure coding? > > > Rhian Resnick > > Assistant Director Middleware and HPC > > Office of Information Technology > > > Florida Atlantic University > > 777 Glades Road, CM22, Rm 173B > > Boca Raton, FL 33431 > > Phone 561.297.2647 <(561)%20297-2647> > > Fax 561.297.0222 <(561)%20297-0222> > > [image: image] <https://hpc.fau.edu/wp-content/uploads/2015/01/image.jpg> > > _______________________________________________ > ceph-users mailing list > ceph-users at lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.ceph.com/pipermail/ceph-users-ceph.com/attachments/20170308/606f6a90/attachment.htm>
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