>I am wondering though, the %util on the disk storage pool is hovering right
>arount 100% while this bkup is occuring.  And its seems to come down a
>few fractions of a percent while the %migrated seems to go up roughly
>the same amount.  I have file caching on on the disk pool, but does
>ADSM only free up disk space occupied by cached files on a as needed
>basis????

My experience thus far shows that ADSM Caching is problematic: it keeps the
storage pool capacity up around 100%, but doesn't react fast enough to
reclaim space when it's needed.  I had an HSM-controlled file system
NFS-exported to another AIX system in order to copy data.  Caching was on
and I kept the high migration threshhold under 50%.  Data copying failed
on "remote file system full", "No space left on device".  I turned off
Caching and copying succeeded.
    Can others with longer-term experience with Caching lend any insights
or advisories on configuration which may make Caching work; or should one
simply stick with 90% high migration values to have a caching effect but
maintain a space margin?
      thanks, Richard Sims, Boston University OIT