Disable the Prefetch and Superfetch Features on Windows Virtual Machines

By disabling the Windows prefetch and superfetch features, you can avoid generating prefetch files and the overhead associated with prefetch and superfetch operations. This action can reduce the growth of linked-clone machines and minimize IOPS on full virtual machines and linked clones.

To disable the prefetch and superfetch features, you must edit a Windows registry key and disable the Prefetch service on the virtual machine.

The following steps apply to Windows 7 and Windows 8. The steps might vary on different Windows operating systems.

Prerequisites

See the Microsoft TechNet Web site for information on how to use the Windows Registry Editor.

Procedure

1. Start the Windows Registry Editor on the local Windows virtual machine.
2. Navigate to the registry key called PrefetchParameters.
   The registry key is located in the following path: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\PrefetchParameters.
3. Set the EnablePrefetcher and EnableSuperfetch values to 0.
4. Click Start > Control Panel > System and Security > Administrative Tools.
5. Select Services and click Open.
6. Double-click the Superfetch service.
7. In the Superfetch Properties (Local Computer) dialog, click Stop.
8. In the Startup type menu, select Disabled.
9. Click OK.