To monitor Windows CPU load

1. Start the Windows Performance Monitor.

   For instructions, refer to your Microsoft documentation.

2. To determine how hard the CPU is working, monitor the % Processor Time counter for the Processor object.

   For % Processor Time, values of 0 to 80 percent are generally safe. Values from 80% to 90% indicate that the system is heavily loaded. Consistent values over 90 percent indicate that the CPU is a bottleneck.

   Spikes close to 100 percent are normal and do not necessarily indicate a bottleneck. However, if sustained loads close to 100 percent are observed, consider tuning the system to decrease process load, or upgrade to a faster processor.

3. To determine how many processes are actively waiting for the processor, monitor the Process Queue Length counter for the System object.

   Sustained Processor Queue Lengths greater than 2 indicate that too many threads are waiting to be executed. To correctly monitor the Processor Queue Length counter, the Performance Monitor must track a thread-related counter. If you consistently see a queue length of 0, verify that a non-zero value can be displayed.

   The default scale for the Processor Queue Length may not be equal to 1. Be sure to read the data correctly. For example, if the default scale is 10x, then a reading of 40 means that only 4 processes are waiting.