Storage I/O Consumption

Hi all,

I'm monitoring my hosts (version 3.5, 4.0 and 4.1) and on the Plan tab I have the Storage I/O Consumption without a maximum value.

It seems like the ESX is not saying VMM how much maximum I/O he can reach. It is normal? Or maybe this feature is working only with vSphere 5 which has the Storage IO Control feature?

Al the other KPI are working correctly.

Many thanks

SR