Moving files from one volume to other volumes in the same storage pool provides a number of benefits.
See Deleting storage pool volumes for information about deleting backed-up, archived, or space-managed data before you delete a volume from a storage pool.
If you want to force the removal of cached files, you can delete them by moving data from one volume to another volume. During the move process, the server deletes cached files remaining on disk volumes.
If you move data between volumes within the same storage pool and you run out of space in the storage pool before all data is moved from the target volume, then you cannot move all the data from the target volume. In this case, consider moving data to available space in another storage pool as described in Data movement to a different storage pool.