I have had a heard time finding a real description or definition of "Overcommitted Allocation" and "Host Overcommitted Allocation", as you can find them in the Planning-->Views-->Virtual Machine Capacity view within vCOps. I have had an equally hard time making this percentage make sense, particularly when it comes to Disk Space.
For example, one of my clusters has Overcomittment Allocation at 94%, with no buffers and not using HA configuration (I removed these pieces to simplify things). This is a small cluster, with 8 hosts, 12 VMFS5 datastores, and 38TB of total disk space, and all VM's using thick lazy zeroed .vmdk's. When browsing all the datastores and account for all space that is consumed, there is 26TB of provisioned space, of the 38TB available, which is only about 68%. The policy for the cluster also has 0% allocation overcommit ratios and I'm running vCOps 5.8.4. In any event, I can't make the 94% make sense. If anyone has any insight into what these two metrics really entail and take into account, it would be very helpful.
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