Monitoring Windows disk load
To use disk performance counters to monitor the disk performance in Performance Monitor, you may need to enable the counters. Windows may not have enabled the disk performance counters by default for your system.
To enable the counters and allow disk monitoring
- Enter the following:
diskperf -y
- Restart the system.
To disable the counters and cancel disk monitoring
- Enter the following:
diskperf -n
- Restart the system.
To monitor disk performance
- Use the %Disk Time counter for the PhysicalDisk object.
Track the percentage of elapsed time that the selected disk drive is servicing read or write requests.
- Monitor the Avg. Disk Queue Length counter and watch for values greater than 1 that last for more than one second.
Values greater than 1 for more than a second indicate that multiple processes are waiting for the disk to service their requests.
See Bypassing disk performance with the SKIP_DISK_WRITES touch file.