Article ID: 975036 - View products that this article applies to.
On Windows Server 2008, you can monitor disk performance from inside a virtual machine or from the Hyper-V root partition. When you monitor performance from inside the virtual machine, you only have access to performance counters that are provided by the guest machine. Therefore, utilization counters are only relative to the virtual object that is being monitored. In this case, counters will sometimes report more physical resource usage than actually exists.
For example, the average disk queue length on the guest machine may report too many I/O requests. This means that all the requests are not queued. Some requests are completed and are on their way back to where the performance data is been collected.
On a Hyper-V server, one of the functions of the root partition (Physical Machine) is to provide monitoring information by using both WMI and performance counters. To obtain more accurate information while you monitor disk performance, you can use the Hyper-V root partition performance counters. You can use the following Hyper-V storage objects and counters that are provided by the root partition to monitor disk performance for the virtual machines:
For more information about how to monitor Hyper-V performance, visit the following Microsoft Web site:
http://blogs.msdn.com/tvoellm/archive/2009/04/23/monitoring-hyper-v-performance.aspxFor more information, click the following article number to view the article in the Microsoft Knowledge Base:
(http://support.microsoft.com/kb/967124/ )Hyper-V performance counters in Windows Server 2008 are displayed incorrectly or report incorrect data when you remotely query the counters from a Windows Server 2003-based computer
Article ID: 975036 - Last Review: November 22, 2010 - Revision: 1.1