Ceph » CephFS

I have next directory structure in ceph fs:

somedir
       subdir1
              == 35K files, every 20MB size ==

I'm using Ceph Bobtail. This directory is mounted from fstab like this:

10.252.0.3:6789,10.252.0.2:6789,10.252.0.4:6789:/ /mnt/ceph ceph _netdev,snapdirname=.cc633faa563cbe671221758ad9c01de3,dirstat,norbytes,nocrc,name=admin,secret=SOMESECRET==,readdir_max_entries=8192,readdir_max_bytes=4194304 0 0

from two hosts:

1st is 32bit host running 3.7.3 kernel with ceph module
2nd is 64bit host running 3.7.3 kernel with ceph module

If I cd to that dir from x64, I can see the contents and can copy files from it to local fs.
If I try to create some subdir inside subdir1 and move a file from subdir1 to subdir1/subdir2 it hangs on all accessing hosts, only complete unmount from all hosts, restart mds fixes.

If I cd to that dir from 32bit, I see empty directory, but can see that directory subdir1 includes 35K files from it's stat.

Sometimes, when I try to cd to subdir1 directory, It hangs randomly. Full umount and restart mds-s fixes it.

When the problem occures, other mounts of ceph (with another subdirs) works well and no problem at all.

I have 3 node/15 osds (5 on each), every on separate drive installation, journal in RAMFS. XFS as backing store for OSD. Also have 3 mons and 3 mds on separate 3 nodes. Every mon writes to SSD. Hosts are connected using 1G/10G mixed.