If you are in a pure TSM environment, meaning the VTL is exclusively used by TSM, how useful is truncating scratch tapes and returning that space to the VTL's pool of free space? Unless you use co-location all volumes are going to be quickly written to their define maximum native capacity. The only exception to that would be TSM db backup volumes. For me, the VTL's short mount/dismount times and using a small size (10GB) for the defined maximum native capacity has meant I do not require co-location. Since my volumes are small even a TSM db backup would not produce much "wasted" space.
So while it is an interesting behavior, in the above environment, how relevant is it? Thanks, H. Milton Johnson -----Original Message----- From: ADSM: Dist Stor Manager [mailto:[EMAIL PROTECTED] On Behalf Of Curtis Preston Sent: Friday, June 15, 2007 4:19 PM To: ADSM-L@VM.MARIST.EDU Subject: Re: [ADSM-L] How to Incorporate a CDL into a TSM environment? John Schneider said: >I can't speak for everybody's product out there, but the EMC CDL (EDL) >releases the used pages from the virtual volume as soon as you begin to >overwrite the virtual volume from the beginning. One thing that does >this is a Label Libvolume. This is the way they all work. And you're right. All you have to do is find new tapes in the scratch pool and label them, and voila!. OR... You can just wait for the tape to get reused by TSM, at which point all its space will get erased then replaced with whatever you write to it next.