Onotsky, Steve x55328 wrote at 14:23 -0400 on May 14, 2009:
 > I agree, but the caveat is that the planner will do its darndest to
 > make full use of the extended capacity of the LTO4 cartridge.
 > 
 > In my case, our backups went from between 5 and 8 hours with LTO2
 > tapes to well over 24 hours in some cases with the LOT4s - same
 > DLEs.  It took some fancy footwork to get it to a reasonable window
 > (about the same length of time as with the 2s but some of the
 > larger DLEs are forced to incremental on weekdays).  This is so we
 > can get the cartridges ready for pickup by our offsite storage
 > provider.

You can lie about your "tape" size in the tapetype, of course.
You can even have different lies for different configurations.

I've always wanted a knob to tell the scheduler to "shoot" for a
smaller percentage of the total tape size, but to go ahead and use
more if needed.  Kind of an average target total size for the dumps.

Maybe there is such a knob these days.  I hope someone will
say if there is.

Lying about the tape size usually works fine.  And it will go over
that declared size if needed - if, for instance, some unexpected
increase in size to a DLE happens after the estimate completes (or for
whatever reason, the estimate is too low).