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%