This article was previously published under Q102020
Disk performance counters, the Diskperf service, must be started priorto the Performance Monitor in order to monitor disk performance. Diskperformance counters are disabled by default.
The impact of the Performance Monitor on the overall performance of asystem is minimal. However, the counters (which are necessary tomonitor disk performance) will have a slight impact to the overallsystem performance. For this reason, these counters are not started bydefault. Therefore, for best system performance, they should bestarted prior to beginning disk performance monitoring and thenterminated.
To enable the Diskperf service, use either of the following twoprocedures.
Choose the Command Prompt icon in the Main group.
At the command prompt, type "DISKPERF -Y" (without the quotation marks) and press ENTER. You will receive the following message:
Disk performance counters on this system are now set to start at boot. This change will take effect after the system is rebooted.
Start Control Panel, choose Devices and change the startup value of Diskperf to Boot.
Restart your computer.
Once the system is restarted, disk performance monitoring is enabled.After monitoring disk performance, you should turn off the Diskperfservice.
Use to following command to disable the Diskperf service:
DISKPERF -N -- This will set the disk performance counters to never start. For best overall system performance issue this command from the command prompt after completing disk performance monitoring.
Other helpful commands that may be issued from the command prompt toassist in disk performance monitoring are:
DISKPERF /? -- Displays help for the DISKPERF command.
DISKPERF -- Displays the current status of the disk performance counters along with help for the DISKPERF command.
Diskperf -YE, the E allows monitoring of all NT Software Fault Tolerant sets that utilize the FTDISK device driver. This does not apply to hardware arrays.
For help with system performance issues in Windows Vista, visit the following Microsoft web page: