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Subject: RE: preventing deadlocks in snapshot directories - unexplained
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I'm sorry - I misspoke in my original post, and I don't think I made clear
what it was I was witnessing.

What I am saying is, I have snapshots that exist _two_ directories deep
off of the mount point, such as:

/.snap/snap_directory1/snapshot
/.snap/snap_directory2/snapshot

and what I am seeing is, if I:

cd /.snap    (note, no snapshots in here)

rm -rf snap_directory1/   (note, deleting a dir containing snapshot)

What happens is, other operations inside of /.snap lock up.  Which is
contradictory to what I expected, and to what you have explained thus far
in response to my original post (many thanks for those responses).  Both
you and I seem to expect that operations would only be locked for the
/.snap/snap_directory1/ directory.

I am going to try to reproduce this ... 

The "solution" I proposed was :

/.snap/snapshot
/.snap2/snapshot
/.snap3/snapshot

Which isn't much different, but it prevents the existence of a
non-snapshot directory that could accidently be put into use, or be a pwd,
or otherwise statted while a snapshot is deleted, etc.

Any thoughts / comments ?