Le 07/08/2015 22:05, Ben Hines a écrit : > Howdy, > > The Ceph docs still say btrfs is 'experimental' in one section, but > say it's the long term ideal for ceph in the later section. Is this > still accurate with Hammer? Is it mature enough on centos 7.1 for > production use? > > (kernel is 3.10.0-229.7.2.el7.x86_64 ) Difficult to say with distribution kernels, they may have patched their kernels to fix some Btrfs issues or not (3.10.0 is more than 2 years old) I wouldn't trust them myself. We are converting our OSDs to Btrfs but we use recent kernel versions (4.0.5 currently), we disabled Btrfs snapshots in ceph.conf (they are too costly), created journals NOCOW (we will move them to SSDs eventually) and developed our own defragmentation scheduler (Btrfs' own autodefrag didn't perform well with Ceph when we started and we use the btrfs defragmentation process to recompress data with zlib instead of lzo as we mount OSD fs with compress=lzo for lower latency OSD writes). In the above conditions, it is faster than XFS (~30% lower apply latencies according to ceph osd perf), detects otherwise silent data corruption (it caught some already) and provides ~10% additional storage space thanks to lzo/zlib compression (most of our data is in the form of already compressed files stored on RBD, actual gains obviously depend on the data). Best regards, Lionel _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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