Some time ago, I encountered a problem () – in the documentation of vmware vsphere sdk you can see – totalLatency is supported by vm and host, but on practice it’s false =(. And only now it has been corrected - . And they (vmware developers) implemented this thing (vm disk latencies) in vSphere 4.1 - . So, you just need to request virtualDisk group metrics instead of disk. That’s really good news, because now you don’t need to install on guest vmware tools or special script that collects this information, now this metrics are supported by new ESX 4.1.