Could you reduce the "Reclamation Processes" count on the storagepool by one 
leaving a tape drive free for migration?

David

-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of 
Roger Deschner
Sent: Wednesday, February 17, 2016 8:43 PM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: [ADSM-L] Migration should preempt reclamation

I was under the impression that higher priority tasks could preempt
lower priority tasks. That is, migration should be able to preempt
reclamation. But it doesn't. A very careful reading of Administrator's
Guide tells me that it does not.

We're having a problem with a large client backup that fails, due to a
disk stgpool filling. (It's a new client, and this is its initial large
backup.) It fills up because the migration process can not get a tape
drive, due to their all being used for reclamation. This also prevents
the client backup from getting a tape drive directly. Does anybody have
a way for migration to get resources (drives, volumes, etc) when a
storage pool reaches its high migration threshold, and reclamation is
using those resources? "Careful scheduling" is the usual answer, but you
can't always schedule what client nodes do. Back on TSM 5.4 I built a
Unix cron job to look for this condition and cancel reclamation
processes, but it was a real Rube Goldberg contraption, so I'm reluctant
to revive it now in the TSM 6+ era. Anybody have a better way?

BTW, I thought I'd give the 7.1.4 Information center a try to answer
this. I searched on "preemption". 10 hits none of which were the answer.
So I went to the PDF of the old Administrator's Guide and found it right
away. We need that book!

Roger Deschner      University of Illinois at Chicago     rogerd AT uic DOT edu
======I have not lost my mind -- it is backed up on tape somewhere.=====