...hopefully some useful VMware related stuff
Watch snapshot delta files commit
Use this command to watch the snapshot delta files commit. If your snapshot files are quite large, virtual center will often timeout on the commiting task, you can use this to watch the progress and confirm it is actually working.
Log into the host with putty over ssh
Type in the following command: watch "ls -Raloghut --full-time /vmfs/volumes/* | grep delta"
Then within virtualcenter or vCenter delete all the snapshots for your virtual machine.
You will see a new delta file create and the old ones dissappear.