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performance monitor

I don't understand Performance monitory.

I have 2 metrics here % CPU and % Disk time.  I would assume that 100% would be the maximum for both.  However as you can see from this graphic it says my disk is at about 2000+ %?  Can someone please explain to me the scales used in perfmon? perfmon results
Watch Question

% Disk Time may exceed 100 percent in the Performance Monitor MMC


This behavior can occur because some controllers allow the operating system to use overlapping input/output operations for multiple outstanding requests. The disk performance counters time the responses by using a 100 nanosecond precision counter, and then report the cumulative statistics for a given sample time. This sample time could go over 100 percent if, for example, you have 10 requests that completed in 2 milliseconds each in a 10 millisecond sampling interval. If you have multiple disks in a Raid arrangement, the overlapped input/output happens because the operating system can read and write to multiple disks, and this could show values that are higher than 100 percent for this counter.

This behavior is by design.


Thanks for that, so basically the metric is useless