Yeah I checked the dump , it it truely the known issue. Thanks 2017-03-08 17:58 GMT+08:00 John Spray <jspray@xxxxxxxxxx>: > On Tue, Mar 7, 2017 at 3:05 PM, Xiaoxi Chen <superdebuger@xxxxxxxxx> wrote: >> Thanks John. >> >> Very likely, note that mds_mem::ino + mds_cache::strays_created ~= >> mds::inodes, plus the MDS was the active-standby one, and become >> active days ago due to failover. >> >> mds": { >> "inodes": 1291393, >> } >> "mds_cache": { >> "num_strays": 3559, >> "strays_created": 706120, >> "strays_purged": 702561 >> } >> "mds_mem": { >> "ino": 584974, >> } >> >> I do have a cache dump from the mds via admin socket, is there >> anything I can get from it to make 100% percent sure? > > You could go through that dump and look for the dentries with no inode > number set, but honestly if this is a previously-standby-replay daemon > and you're running pre-Kraken code I'd be pretty sure it's the known > issue. > > John > >> >> Xiaoxi >> >> 2017-03-07 22:20 GMT+08:00 John Spray <jspray@xxxxxxxxxx>: >>> On Tue, Mar 7, 2017 at 9:17 AM, Xiaoxi Chen <superdebuger@xxxxxxxxx> wrote: >>>> Hi, >>>> >>>> From the admin socket of mds, I got following data on our >>>> production cephfs env, roughly we have 585K inodes and almost same >>>> amount of caps, but we have>2x dentries than inodes. >>>> >>>> I am pretty sure we dont use hard link intensively (if any). >>>> And the #ino match with "rados ls --pool $my_data_pool}. >>>> >>>> Thanks for any explanations, appreciate it. >>>> >>>> >>>> "mds_mem": { >>>> "ino": 584974, >>>> "ino+": 1290944, >>>> "ino-": 705970, >>>> "dir": 25750, >>>> "dir+": 25750, >>>> "dir-": 0, >>>> "dn": 1291393, >>>> "dn+": 1997517, >>>> "dn-": 706124, >>>> "cap": 584560, >>>> "cap+": 2657008, >>>> "cap-": 2072448, >>>> "rss": 24599976, >>>> "heap": 166284, >>>> "malloc": 18446744073708721289, >>>> "buf": 0 >>>> }, >>>> >>> >>> One possibility is that you have many "null" dentries, which are >>> created when we do a lookup and a file is not found -- we create a >>> special dentry to remember that that filename does not exist, so that >>> we can return ENOENT quickly next time. On pre-Kraken versions, null >>> dentries can also be left behind after file deletions when the >>> deletion is replayed on a standbyreplay MDS >>> (http://tracker.ceph.com/issues/16919) >>> >>> John >>> >>> >>> >>>> >>>> Xiaoxi >>>> _______________________________________________ >>>> ceph-users mailing list >>>> ceph-users@xxxxxxxxxxxxxx >>>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com