I discussed this with ADSM support a year or more ago ---
reclamation does a poor job of deciding which volume to pick first.
If it were smarter, it would pick the volume with smallest utilization,
because a tape that's 0.5% full can be copied in a few minutes, but a
tape that's 40% full may take an hour.

But it's not smarter.  it picks (something like) the volume with the
largest total capacity.

So if you or your script do that low-utilization volumes first, you'll
recover more tapes quickert than reclamation will.

That said, however, I always use reclamation, save the
low-utilization-first trick for emergency situations, because in the
long term, it gets the same thing done, and it may handle copy pools
more efficiently.

Why yours was running 23 hours a day - gee.  Did you have the threshold
set to say 10%? If it's too low, TSM will spend all day copying tapes
without getting much result.



"Slaughter, Bill" wrote:
>
> When I was running reclamation, it was running about 23 hours a day till we
> would cancel it to run the Daily DB Backup for OFFSITE. I had many OFFSITE
> tapes that would be below the reclamation percentage, they hardly ever
> seemed to be freed up.
>
> I use "MOVE DATA" because I found out that I can get it to process in much
> less time than reclamation. Thus my tape drives are free to do other
> activity. i.e. My move data script runs in about 1-3 hours (Depending on
> number of tapes) and I have a separate script for the ONSITE tapes and
> OFFSITE tapes.
>
> I hope this clears up the myth of "MOVE DATA" being less efficient than
> reclamation.
>
> Bill

--
Mr. Lindsay Morris
Mr. Lindsay Morris
Gresham Enterprise Storage
lmorris AT openmic DOT com
606-253-8000