2. Although ESXI 4.1 allows you to limit the 1 - 2.5GHz vCPU to 4000GHz, it does not make any sense to put this limit in. The limit would be only useful where you are tryiing to allow for f...
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2. Although ESXI 4.1 allows you to limit the 1 - 2.5GHz vCPU to 4000GHz, it does not make any sense to put this limit in. The limit would be only useful where you are tryiing to allow for fractional vCPUs - like <1 or 1.5. ?? The first part is correct. Much like memory limits, they only affect the VM if the limit is set lower than the allocation. Otherwise, the allocation already "limits" the VM. I don't think the second part would work like that. Either a VM is using a core or it is not. For example, if you allocated two vCPUs and limited it to 3 GHz, it would still use 2 vCPUs regularly. However, if it attempted to use more than 3 GHz, then it would get limited in its consumption. Because of both these facts, there's only two potential use cases for CPU limits that I can think up at the moment: Testing purposes. If you want to see the impact of CPU contention (CPU ready) on a virtual machine, CPU limits are great for that. If you have a VM that starts consuming all its allocated CPU and starts to impact the performance of other virtual machines. CPU limits can be created and removed instantly, without having to power off the VM.