I did administer a backup server with multidisk LVM volumes and had a persistent problem in one volume with XFS. I even reported the problem to XFS development mailing list. I couldn't find no evident, where the problem came from eventually. My final conclusion was that mkfs.xfs had some bug at the time the volume was created, since newer XFS volumes never got similar problem and after couple upgrades to xfs utilities newer xfs_repair pushed the problem over the edge to non existence.
Lesson learned: it pays to keep data on smaller volumes although it is very very tempting to stuff data to ever bigger volumes and postpone the headache in splitting and managing smaller volumes.