Allen,

We opened a PMR that sounds like it might match your observations.  We have way 
too many volumes in what I call "barely filling" status, with no explanation of 
how they got that way.  APAR IC76192 was opened for this:
http://www-01.ibm.com/support/docview.wss?uid=swg1IC76192

..Paul

At 04:17 PM 2/6/2012, Allen S. Rout wrote:
>So, I've got an offsite machine which exists to accept remote virtual
>volumes.  For years, now, the filling volumes have behaved in a way I
>thought I understood.
>
>The tapes are collocated by node.  There are about 20 server nodes which
>write to it.
>
>My number of filling volumes has rattled around 50-60 for years;  I
>interpret this as basic node collocation, plus occasional additional
>tapes allocated when more streams than tapes are writing at a time.  So
>some of the servers have just one filling tape, some have two, and the
>busiest of them might have as many as 6 (my drive count).
>
>Add a little error for occasionally reclaiming a still-filling volume,
>and that gives me a very clear sense of what's going on, and I can just
>monitor scratch count.
>
>Right now, I have 190 filling volumes.
>
>None of them has data from more than one client.
>
>I have some volumes RO and filling, and am looking into that, but it's
>20 of them, not enough to account for this backlog.  Those are also the
>only vols in error state.
>
>I've been rooting through my actlogs looking for warnings or errors, but
>I've never had occasion to introspect about how TSM picks which tape to
>call for, when it's going to write.  It's always Just Worked.
>
>
>Does this ring any bells for anyone?    Any dumb questions I've
>forgotten to ask?  I don't hold much hope for getting a good experience
>out of IBM support on this.
>
>
>- Allen S.Rout


--
Paul Zarnowski                            Ph: 607-255-4757
Manager, Storage Services                 Fx: 607-255-8521
719 Rhodes Hall, Ithaca, NY 14853-3801    Em: psz1 AT cornell DOT edu