Yes, and I think it's a myth (namely the part that disabling superfetch is a performance tuning myth).shoma wrote:Have you ever heard of "tuning myths"...?
http://www.windows7hacker.com/index.php ... windows-7/
That's based on (1) actually testing and (2) understanding of how disk caching and memory managers work.
Superfetch is designed to improve the situation where you come to work every morning, start your Excel and Outlook and work on the same few spreadsheets from 9 to 5, until you shut down your computer and go home, only to repeat it next day. For this purpose it works remarkably well and if that's what you do, sure keep it on. It will preload Excel and Outlook and the same few spreadsheets for you before you actually open them, and everything appears to be fast.
Unfortunately as soon as your disk access patterns are even slightly less predictable, it tends to cause a lot of "predictive" reads that in practice end up throwing out useable caches. If you additionally keep your computer running (you can suspend if you want, the point is to avoid cold starts unless you're applying patches) then after a day or two (in practice usually faster than that), everything should be in caches. At this point you should not need to touch the disk AT ALL (assuming your system has sensible amount of memory, ofcourse). When you start your browser, there should be no disk reads, so there's nothing for Superfetch to prefetch. Unfortunately, try that with Superfetch, and you'll still be reading the disks all the time.
In Win7 they improved it a bit; it seems not to be quite as aggressive. In Vista it's absolute bullshit.
