Errr... yeah - them too...

The problem will be when you've allocated huge vdisks for all your
production systems based on the old "Swap = 2X main memory" ROT. In that
example - you're basically tripling your overcommit ratio by including the
vdisks. This also can have a large cost in terms of CP memory structures to
manage those things.

The current guidance is a smallish vdisk for high priority swap space, and a
largish low priority real disk/minidisk for occasional use by badly behaved
apps.  Swapping to the vdisk is fine in normal operations, swapping to the
real disk should be unusual and rare.

So - overcommit ratio is calculated as follows:

( Sum ( guest virtual storage sizes ) + Sum ( vdisk sizes ) )  / central
storage

Anything else I've forgotten?

-- 
Jay Brenneman

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