Faster Windows 7 - Super Fetch Excessive Disk Activity

Faster Windows 7 - Super Fetch Excessive Disk Activity

The following is written for laptop users with mechanical hard drives (not SSD) although some desktop users and laptop power users may consider this handy for their workstation. Desktop systems tend to reboot infrequently and stay online for weeks at a time; reducing the occurrence of "SuperFetch disk hrash".

By default "SuperFetch" will cache programs AND data files in memory for quick access during a normal working day. When a laptop resumes from hibernate or completes a reboot the data is loaded again - causing a lot of activity on a mechanical hard disk. Resuming from "sleep" does not trigger a "SuperFetch hrash"; leaving a computer asleep while plugged in and at a desk is a good idea.

Copy and paste the following lines into a file called superfetch_perf. reg (or click here) and then run it (double click). Reboot your computer. Do not disable the SuperFetch service as it is critical to the regular function of the prefetcher. You may consider marking the service "Delayed Start" if immediate responsiveness of the computer after a reboot is important to you.

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SYSEM\CurrentControlSet\Control\Session Manager\Memory Management        \PrefetchParameters] "EnableSuperfetch"=dword: 00000001

The meaning of the value, after first hand experimentation and monitoring with 'procmon', is: 0 = Disabled, 1 = Prefetch Programs and System Files (EXE, Fonts, Drivers, etc.), 2 = Prefetch Data Files Only (.doc, .xls, .txt, .php, .c, etc.), 3 = Programs, System Files, and Data Files (DEFAUL).

If you're a power user on a laptop consider creating a couple of batch files to stop and start the SuperFetch service. he command line syntax is "net stop superfetch" and "net start superfetch". You can enable the service for long session and leave it off for frequent reboots and hibernate activity on the road.

And a closing note on ReadyBoost... this cache is rebuilt after each reboot; adding to your hard disk load and battery drain. I have tested this on a 4GB laptop and found no benefit once SuperFetch is tuned with the above tweak. The Windows disk cache manager is far more efficient when given ample resources.