Looking in the "Magstar MP 3575 Tape Library Dataserver: Multiplatform 
Implementation" Redbook, p.136, the hardware compression settings are 
controlled from AIX. The default setting is compression "on".  Page 146 
indicates that format=3570C uses compression. 

However it SHOULD be done, the fact remains that Nancy is not getting any 
compression. Someone may have modified the device settings. By modifying the 
device settings and changing ADSM to format=drive (this is not really 
necessary, but useful for adding XLC cartridges), this should give her what she 
wants.

Miles

>>> Richard Sims <rbs AT BU DOT EDU> 29-Nov-00 11:26:00 AM >>>
>we have the exact same hardware. Your problem is most likely because you =
>haven't enabled compression. I would recommend hardware compression. To =
>turn on the hardware compression:
>smitty devices
>tape devices
>Change / show characteristics of a tape drive
>select your drive
>select Use hardware compression on tape =3D yes

Wait a minute...TSM is supposed to set tape drive characteristics, among the
drives that it directly supports, per administrative specifications: it should
not be necessary to forcibly alter drive characteristics with the product.
Doesn't the DEVclass FORMAT=3570C take care of this?
   Richard Sims, BU