On Jan 5,  8:19am, Mark Linehan wrote:
<=> Subject: To Collocate or Not to Collocate?
<=>Big question, I finally got reclamation working on our system. It's amazing
<=>how many tapes change from full to filling when you change reclamation from
<=>60 to 30! Well, now that this is behind me, the next question I would like
<=>to throw out is "How usefull is collocation?" Should I enable it? Will it
<=>save me that much time on retores? How much longer will it take to perform
<=>backups with collocation enabled?? I have to A S S U M E it is going to
<=>take a long time for collocation to first take place when it is enabled.

Not really. Collocation will only take effect for data stored on NEW tapes. In
other words, what is already on your tapes now will not be moved in order to
enforce collocation.

If you want to collocate what is already there, you can use the MOVE command to
move the contents of your already used tapes. During its processing, MOVE will
respect the collocation directives as defined at the start of the move. You can
achieve similar results by enforcing a migration from a tape pool to a lower
tape pool, where collocation is enabled.


<=>
<=>Mark
<=> End of excerpt from Mark Linehan


--
Regards
Regards

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