Ceph » CephFS

Looks like a setattr and a create:

ubuntu@plana72:~$ sudo ceph --admin-daemon /var/run/ceph/ceph-client.0.19374.asok mds_requests { "tid": 1219,
"op": "setattr",
"path": "#100000001f5",
"path2": "",
"ino": "100000001f5",
"target_ino": "100000001f5",
"hint_ino": "0",
"sent_stamp": "2013-04-17 03:00:24.344943",
"mds": 0,
"resend_mds": -1,
"send_to_auth": 0,
"sent_on_mseq": 0,
"retry_attempt": 0,
"got_unsafe": 1,
"uid": 0,
"gid": 0,
"oldest_client_tid": 1211,
"mdsmap_epoch": 0,
"flags": 0,
"num_retry": 0,
"num_fwd": 0,
"num_releases": 0}{ "tid": 1220,
"op": "create",
"path": "#100000001f5\/fstest_b5c1034e024d6f8e44a438e430391c84",
"path2": "",
"ino": "100000001f5",
"dentry": "fstest_b5c1034e024d6f8e44a438e430391c84",
"hint_ino": "0",
"sent_stamp": "2013-04-17 03:00:25.360236",
"mds": 0,
"resend_mds": -1,
"send_to_auth": 0,
"sent_on_mseq": 0,
"retry_attempt": 0,
"got_unsafe": 0,
"uid": 0,
"gid": 0,
"oldest_client_tid": 1219,
"mdsmap_epoch": 0,
"flags": 0,
"num_retry": 0,
"num_fwd": 0,
"num_releases": 0}

Marked #4741 as a duplicate of this bug. It looks like setattr is the culprit. I was able to generate a core file of the mds while it was in this state, and the only request sitting in mds->mdcache->active_requests is the setattr which the client is waiting for (and already has an unsafe reply to). I have the dump of the mds cache as well, all that it shows for the inode the setattr is operating on is that its dirty.

Looks like a client bug, it may add cap releases to the replay requests. (encode_cap_releases() should be called when creating request, instead of sending request)

Yeah, we've discussed this some on github around wip-4742 and on irc. :)