Working with the Windows Prefetcher

What is the Prefetcher? It is a very nifty component of Windows XP that can seemingly read your mind and will start loading your program seconds before you actually start it to boost the startup of the application.

Although the Prefetcher keeps track of the applications that you run, creates optimized copies of them, and stores them in a special cache on your computer, this special cache is simply a location on your hard disk that has no, or very few, file fragments and stores application setting files. The next time you start your program,Windows will load it out of the Prefetcher cache, which is what causes the application to start up quicker.

If you really want to investigate this matter further, take a look at the Prefetcher cache. It is located in the Windows directory inside the Prefetcher folder. You will notice that the cache does not have an exact copy of each application because the files are a fraction of the size of the actual application executable file. Rather, it just has fragments of applications that are used to boost the performance of the startup.

The Prefetcher constantly monitors what applications you are running, even during parts of the bootup. That information is then passed on to help the disk defragmenter optimize the boot files.

The Prefetcher is a very complex component. The majority of the settings can be changed by hacking the registry; however, due to a lack of documentation on these settings, changing them without any guidance would be very risky. Thankfully, a few tips have surfaced in the vast documentation buried at Microsoft's site and revealed in Microsoft's applications.

The paragraphs that follow will explore some of these.