This is an extract of the Adminstrative Guide (Changing Collocation).

"After you define a storage pool, you can change the collocation setting
by updating the storage pool. The change in collocation for the pool
does not affect files that are already stored in the pool. 

For example, if collocation had been off for a storage pool and you turn
it on, from then on client files stored in the pool are collocated.
Files that had previously been stored in the pool are not moved to
collocate them. As volumes are reclaimed, however, the data in the pool
tends to become more collocated. You can also use the MOVE DATA command
to move data to new volumes to increase collocation, if you are able to
afford the processing time and the volume mount activity this would
cause."

 Ruddy Stouder
System Engineer
I.R.I.S.
Rue du Bosquet 10 - Parc Scientifique de Louvain-La-Neuve
B- 1435 Mont-Saint-Guibert
ruddy.stouder AT irislink DOT com
http://www.irislink.com
Tel: +32 (0)10 48 75 10  -  Fax: +32 (0)10 48 75 40