[...]Let's talk about Deduplication first. As we've all known for some time, a Best Practice of ours is to stuff as many VM's as you can into a single Datastore [volume] in order to get the highest returns on deduplication. Users can see as high as 80%+ space returned (I know, I was one of them, and did) on their VM's by collectively placing them in the same container with no performance penalty for doing so. Moving data [i.e. vmdk's] between volumes will "un-dedupe" that data being moved, and you will have to re-run the original deduplication scan on that new volume in order to re-coop those savings after the move.[...]
Thank you Nick!
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