Jeff G Kloek wrote, in part:

I've just begun to take over this environment from the admin who left.
I have a large number of filespaces across a lot of my systems that have
not been a part of these systems for years.
I'm wondering what governs TSM keeping those filespaces out there. ...

*SM never expires file spaces; they mark files to be expired when a
backup of their file space is done.

So if you just stop backing up a file space (or all file spaces of a
node), *SM will expire the inactive files (according to your policies),
but will keep the "active" files (files seen on last backup) forever.

Solution: (1) "delete filespace NODENAME *" for each node for which the
backups are no longer needed.  These will start background processes to
complete the deletions.  Once all file spaces for a node are gone, you
may (2) "delete node NODENAME".  NB: if there are many files to be
deleted and you don't have a lot of log space, do the deletions a little
at a time, and not when other long-running processes are in operation.

Hope this helps, wayne