In spite of the name 'virtual memory' the paging file is really just a chunk of reserved hard drive space where data may be written and retrieved as needed. Since the paging file and operating system files are by default located on the same drive, concurrent access to both locations is impossible. One or the other has to wait, slowing down overall system performance...

Originally Posted by Mastertech

This is actually a Myth and will reduce performance:

XP Myths

Originally Posted by CMNetworx

The reduction in performance is something you will probably never notice, Keep in mind every time you run an application for the first time windows is creating a .pf file, When the max of 128 .pf files it starts removing the older/unused ones. Which means when you run an app that you haven't ran for a while it will once again recreate the .pf file., So clearing out your prefetch is not going to slow down your computer as detrimentally as some are making it sound.

Im not sure who has ever had this take up 100% of the processor unless its norton or mcafee trying to scan something (choke choke..)

One thing you should definitely clear out is your temp folder

c:\documents and settings\username\local settings\Temp

It is not uncommon that spy ware will run entirely out of the temp folder because it is not automatically cleared like it should be considering its called a temp folder..

Originally Posted by Mastertech

Don't state nonsense. If Windows now boots in 35 seconds and you delete the prefetch files and it then boots in 60 seconds, you will not notice this? If an application loads in 10 seconds but you delete the prefetch files and it then loads in 20 seconds, you will not notice this? The larger the application and the slower your computer the more "you will notice it". How much you will "notice" is dependent on MANY factors, including the speed of your HD, the HD interface speed, the amount of RAM in your system and the application loading. The fact remains you want your applications to load as quickly as possible and there is NEVER any reason to clean the prefetch folder.

Correction, when the 128 limit is reached, all but the most used 32 prefetch files are flushed. This is based on information stored in the prefetch files. Thus these 32 most used application's performance would NEVER be affected. When you manually delete the folder, you delete ALL of them including the 32 that Windows would leave for your common applications. And yes the file is recreated but BEFORE it is recreated the application loads SLOWER! Why? Because you felt like cleaning the folder for no reason! Leave the folder alone and let windows take care of it.

Clearing out the temp folder is not a way to clean spyware. All modern malware is very resilient to being removed, especially by simplistic suggestions like this. You need to run scans to make sure you are clean. All cleaning the temp files does is increase available disk space.

Boot Prefetching
Windows XP speeds up system boot by observing the code and data needed each time the system is booted and prefetching the necessary file contents early in the boot process. This prefetching is not done until the third boot of the system, when sufficient information is available to make the prefetching most effective. The files observed during system boot will be used in the disk layout process mentioned above.

Application-Launch Prefetching
Windows XP also uses prefetching when launching applications. The files and the contents of the files accessed by each new process are observed and recorded. No prefetching can be done for the first launch of an application, so first launches are often considerably slower than subsequent launches. About 85% to 90% of the improvement is realized after just one launch of an application, with the remaining speed improvement coming after the system has had an opportunity to adjust the disk layout with information specific to this application.

Originally Posted by CMNetworx

Listen, I'm not saying that someone should clean their prefetch daily or anything like that, I am saying that My results with the prefetch have been that clearing out the prefetch has not increased MY boot times. In the event that someone does clean out their prefetch and it increases their boot times, it is no big deal, because within 3 reboots they will be back to normal, In the event of someone having a slower boot obviously it would NOT be advisable to keep cleaning the prefetch.

I have done boot speed testing with bootvis before, but I run linux now, and I am not going to dig up my old hd with xp on it for the sake of an argument. So, for this conversation, I am ending saying that I am Not recommending that everyone clear their prefetch, especially on a regular basis. I am saying that doing so did not effect my boot times, and if it effected yours, a few boots later it will be back to normal.

I am not going to post on this topic again, as it is not really that important..