OverSized VM’s – how to detect them using VMware CapacityIQ
i visited a client which complained about bad behaving VM’s, so I took the liberty to install the recently released VMware CapacityIQ in eval mode (the product only works on VI3 as of now)
Guess what, most of the VM’s were overspec’d with not needed virtual CPU’s (and RAM) which eventually leads to high CPU ready time values..
What the sys admins normally don’t get is when they are trying to be nice to the team they just recently P2V their server which asked them to provide the “exact” resources they had prior for their server being virtualized, they are actually hurting them ! (a good example will be a quad-cpu physical server which used to reside on an older intel CPU generation box than the new “Nehalem” ESX it sits on now as a VM, which will gladly run as a dual vCpu VM)