idk - based on my read, and reading this:

Quote:


Here is an excerpt from Ryan Myers, a developer on Microsoft's Windows Client Performance Team:

XP systems have a Prefetch directory underneath the windows root directory, full of .pf files -- these are lists of pages to load. The file names are generated from hashing the EXE to load -- whenever you load the EXE, we hash, see if there's a matching (exename)-(hash).pf file in the prefetch directory, and if so we load those pages. (If it doesn't exist, we track what pages it loads, create that file, and pick a handful of them to save to it.) So, first off, it is a bad idea to periodically clean out that folder as some tech sites suggest. For one thing, XP will just re-create that data anyways; secondly, it trims the files anyways if there's ever more than 128 of them so that it doesn't needlessly consume space. So not only is deleting the directory totally unnecessary, but you're also putting a temporary dent in your PC's performance.




that is an excerpt from here:

http://blogs.msdn.com/ryanmy/archive/2005/05/25/421882.aspx

I still dont understand why purging the prefetch would improve performance - in fact, based on the information you provided - the prefetch gets "trained" and "optimized" as time goes on (through smart defragging etc) ... I figure that purging the prefetch you would actually "loose" this streamlining that has occured over many reboots.

-Shawn