Vmware CPU LATENCY Counter ON ESXI 5.0.
Posted on 2013-05-10
CPU LATENCY Counter ON ESXI 5.0.
I am having trouble understanding the results from the latency counter on the vcentre for our guest VM.
My understanding of the latency counter is that it will increase when there is contention for physical CPU resources and that it is a measurement of percentage of time that a guest has to wait to get access to the CPU resource. However, all our hosts have more CPU physical cores than the total number of VCPU’s of our guests. Therefore, if my understanding is correct, there should be minimal latency and there should be no contention for physical CPU resources. We are seeing a number of guest VM wares with a latency of above 10% which I have read shows significant degradation of performance.
However, our CPU Ready counter are well below 500 milliseconds. Can anyone shed any light as to why this might be the case?