When I've done it the virtual tape space was similar to that used by a
Testing today with a 73 GB library on a V5R4 system.
Original library = 73 GB
Save File = 73 GB (a bit smaller than the original library, less than
1%, took 19 minutes.)
Image Files for virtual tape = 73 GB (again a bit smaller than the
original library, less than 1%, took 20 minutes.)
Senior IBM Support Specialist
From: John McKee [mailto:jmmckee@xxxxxxxxxxxxxx]
Sent: Wednesday, September 03, 2008 1:45 PM
To: Midrange Systems Technical Discussion
Subject: Virtual tape
To back up 100G of DASD to virtual tape, would you need 100G of DASD for
the virtual tape? Or possibly a better question: Does virtual tape
utilize data compression, thus not requiring quite as much space as if
data was simply copied disk to disk?
How would the size be calculated?
How does virtual tape compare to using a save file or multiple save
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