One way to significantly improve Windows 10 performance is to use an Optane device as

a resource for the SuperFetch cache management technology. SuperFetch itself has two goals: to decrease the time to boot the system and to speed up the loading of commonly used applications. In order to do this SuperFetch stores .pf files in the folder

Windows/Prefetch. The .pf and the directory name are homages to Prefetch, which was SuperFetch’s Windows XP predecessor. To read the .pf files we recommend WinPrefetchView (currently version 1.35) – found at



The top panel gives a list of all the files in the Prefetch directory. The Created Time and Modified Time columns allow you to confirm a program to be optimized is a reasonably current version. Of additional interest is the file size.

Clicking a filename in the top panel gets the bottom panel filled with the files that need to be loaded to start your application. For an external application like Firefox you are unlikely to have much choice about the components that are needed. In your own application it is worthwhile to examine what files are needed.


Of additional interest is the filename NTOSBOOT-B00DFAAD.pf filename, which can show you the list of files that are loaded during Windows boot process. You may wish to turn on or off Windows features in order to indirectly manage Windows load time. Our application is named SAITO. It is under active development, so there were different versions as can be seen here inside the red box. For the most part, in this case the .pf files for the older versions of the EXE can be deleted without harm. It would not hurt to use WinPrefetchView to check what files were being loaded. For developers: we advise NOT analyzing the VSHOST versions of your executable as the contents to be loaded will change when you run using the EXE.