Does the data representing VM %CPU ready times display a single vCPU's ready time, or a summation of multiple vCPU %CPU ready times?
The VM (%) percent ready time is an average of the percent ready time values for that VM's processors (vCPUs).
We get the counter "ready" from the CPU counters(http://pubs.vmware.com/vsphere-51/index.jsp#com.vmware.wssdk.apiref.doc/cpu_counters.html).
The raw counter is the ready time of each vCPU in milliseconds, then we calculate the percentage of ready time for each vCPU.
The formula is: (CPU summation value / (< interval in seconds> * 1000)) * 100 = CPU ready %, and then we calculate the average percentage ready time, the formula is sum(percent ready of each vCPU)/(number of vCPU).