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Hey, all.  I've got a VM -- this is in Juno -- which du shows as using 
152 GB on the compute node's disk.  In the VM, itself, it says it's 
using 39 GB of an 80 GB volume.  So, clearly, that sparse file has 
gotten crazy huge with un-reclaimed stuff.  I seem to recall doing 
snapshots and then defragging them, "back in the day," but I have no 
idea if there's a way to do that to an instance *without* snapshotting.  
So:
* If I snapshot it, can I then just defrag the snapshot and then make 
use of it to bring my system back?
* Even better: is there a way to defrag the on-disk VM files without 
snapshotting?

Thanks...

-Ken