In virtualization environments, storage performance has been a key area to watch. Microsoft has a free tool called Xperf that can help you gather and analyze performance issues. Xperf is one of Microsoft's hottest diagnostic tools. It collects event trace information from components of the operating system and then displays the data in a graphical format. Powerful graph options allow you to quickly pinpoint any storage bottlenecks, along with the detailed data in a tabular format.
There are a couple of articles on Petri.co.il that step you through all you need to know about setting up information gathering and analyzing data for storage performance.