>I always thought that hardware compression was turned on at the
>drive-level, and that all you should do in TSM was use the FORMAT=DRIVE as
>the setting in TSM.
>
>Are you saying that I'd be better served by setting FORMAT=3590H-C???

Hi, Lisa - No.  As the documentation states, FORMAT=DRIVE will attempt to
           utilize the drives to their maximal capabilities.
I pointed out the 'C' designation to demonstrate that the server controls
drive settings; specifically, compression.
In the early days of FORMAT=DRIVE, it was sometimes unreliable, and the
customer had to utilize FORMAT=____C to actually get compression.  And
you may run into issues when you have mixed-capability drives defined in
the Devclass.
It never hurst to perform an 'lsattr' or equivalent to verify that the
drive is operating in compressed mode.  Seeing all the drive settings is,
in any case, educational: I learned a few things by checking what they
were about.

  Richard