Hi Loic, That is a nice idea. And if I then use newfs against that replicated cache pool, it'll work reliably?
Kind regards, Erik. On 06/19/2014 11:09 PM, Loic Dachary wrote: > > > On 19/06/2014 22:51, Wido den Hollander wrote: >> >> >> >> >>> Op 19 jun. 2014 om 16:10 heeft "Erik Logtenberg" >>> <e...@logtenberg.eu> het volgende geschreven: >>> >>> Hi, >>> >>> Are erasure coded pools suitable for use with MDS? >>> >> >> I don't think so. It does in-place updates of objects and that >> doesn't work with EC pools. > > Hi Erik, > > This is correct. You can however set the replicated pool to be the > cache of an erasure coded pool. > > https://ceph.com/docs/master/dev/cache-pool/ > > Cheers > >> >> >>> I tried to give it a go by creating two new pools like so: >>> >>> # ceph osd pool create ecdata 128 128 erasure # ceph osd pool >>> create ecmetadata 128 128 erasure >>> >>> Then looked up their id's: >>> >>> # ceph osd lspools ..., 6 ecdata,7 ecmetadata >>> >>> # ceph mds newfs 7 6 --yes-i-really-mean-it >>> >>> But then when I start MDS, it crashes horribly. I did notice >>> that MDS created a couple of objects in the ecmetadata pool: >>> >>> # rados ls -p ecmetadata mds0_sessionmap mds0_inotable >>> 1.00000000.inode 200.00000000 mds_anchortable mds_snaptable >>> 100.00000000.inode >>> >>> However it crashes immediately after. I started mds manually to >>> try and see what's up: >>> >>> # ceph-mds -i 0 -d >>> >>> This spews out so much information that I saved it in a >>> logfile, added as an attachment. >>> >>> Kind regards, >>> >>> Erik. <mds.log> >>> _______________________________________________ ceph-users >>> mailing list ceph-users@lists.ceph.com >>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >> _______________________________________________ ceph-users >> mailing list ceph-users@lists.ceph.com >> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >> > _______________________________________________ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
