VMinator, I am sorry to say that you will not be able to predict the exact amount of data loss in bytes or in number of WRITE IO commands. It depends on the number of outstanding WRITE commands at the time of failure. In case of ALL PATH DOWN condition, if your VM recover within the timeout value which Guest Operating System (GOS) can tolerate (Refer to OS documents for exact timing details), then GOS will take care of retrying IO operation. If you hit a APD (Permanent Device Loss - PDL), with IO on wire, ie, not committed you will see data loss. But again, as I said you will not be able to predict the exact IO loss.
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