On Nov 30, 2004, at 9:58 AM, Johnson, Milton wrote:
...Needless to say, I disagree with the statement that TSM doesn't appear to be a good fit for a VTL. Remember a VTL is just a library that can mount/unmount a tape in less than one second and read/write to the tape at disk speeds. Why wouldn't TSM work well with a library on steroids? ...
Thanks for sharing your experience with VTL in a TSM environment: it's helpful to have the perspective of experience. As we've seen in past tape vs. disk discussions, though, don't regard "disk speed" as some kind of ultimate data processing I/O attainment: high performance tape technologies streaming to sequential media can in many cases out-pace disk throughput. It is in mounting and tape positioning that tape is a poor performer relative to disk, where one can wait a minute or more before I/O can proceed. That's were VTL shines.
Richard Sims
