SuperFetch Questions

Hi,
How exactly does SuperFetch work? I mean I've heard that it makes your disk thrash over and over again and takes up all your RAM.

And is it actually useful for having on a laptop? Battery life diff with it on/off?

Well, if it does take up a lot of RAM, like most of it, does it automatically free it up, and fast enough, if your decide to launch a large RAM hungry app?

 

You can search my many comments on the matter. It's a feature to hide Vista's inefficiencies. I have always turned it off. Superfetches main benefit is on first booting the OS. Once you load or write something into memory it's there when you want to recall it.

Vista's Memory Management system works the same with or without Superfetch ON. Memory still loads and unloads the same although not as dynamic "annoyingly" with Superfetch on.

 

Shouldn't make your disk "thrash" too much, since it uses the RAM, the battery life may be a little worse but it shouldn't be noticeable.
I does use alot of RAM, and will give it up for most apps, however, microsoft virtualpc 2007 doesnt like it, as it checks the RAM, and if there is not enough free space you cant launch the VM as it does not take space off superfetch, but most thing work with it.

 

In very brief, summary form, superfetch uses algorithms to determine what code/data you're most likely to use on a frequent basis, and preloads that code/data into RAM in anticipation of your using it. As a result, it will increase the use of your hard drive, which may, or may not, result in disk thrashing, depending on what you use, how much RAM you have, and how fragmented your drive is, among other things.

It generally uses as much available RAM as possible while still leaving enough for your typical usage habits. If you were to suddenly load up a huge app that hadn't been prefetched (e.g., because you rarely use it), the RAM into which stuff had been prefetched will simply be turned over to the application, with little or no degradation of that app.