You may notice alerts from the ESX Workload monitor indicating that the Percent Used for a specific VM instance is greater than 100%. This is a valid scenario alerting that the instance is using more than its entitlement of CPU resources.
...
...
Example:
...
...
Notification type: Problem 23/Jun/2010 08:31
...
...
Host: esx01 (OK)
...
Service: ESX hosts monitor (member)
...
Service State: CRIT
...
Output: Percent Used: 103.8% >= 75%