Achmatim.Net

In Windows operating system environment such as Windows XP and Windows Vista system, there is always a file named hiberfil.sys created and existed in the system root drive on boot disk. The hiberfil.sys is large and big in size, always as big as your system physical memory (RAM) size. For example, if the computer have 2 GB of DRAM memory, the hiberfil.sys file size will also be around 1.99 GB in size, taking up precious hard disk space, and in worse case increase fragmentation on the drive.

hiberfil.sys is a file that Windows system creates whenever the computer goes into hibernation mode. When system hibernates, the system state of the computer is preserved by storing a copy of all data in the memory in hiberfil.sys file located on your local disk, so that when the computer restarts, the information can be read into memory to restore the state as of exact state when computer starts to hibernate. That also explains why the size of hiberfil.sys file is always same size with computer's memory size.

If you have ever used hibernation feature in XP and Vista, the hiberfil.sys file will be created. Actually, Windows kernel reserves hiberfil.sys file and allocates space equivalent to memory size to it when installing Windows and enables hibernate ability by default, thus the file exists too even if you never put system into hibernation mode. However, when the computer wakes up from hibernation, the hiberfil.sys file is left on the hard disk and not deleted. If you no longer use the hibernate feature of Windows XP and Vista, the safest way to remove and delete hiberfil.sys from the hard disk is to turn off and disable hibernation function.

How to Disable Hibernation in Windows XP

1. Go to Control Panel, click on Performance and Maintenance link, then run Power Options applet.
2. Go to Hibernate tab.
3. Uncheck and untick the Enable hibernation option.
4. The hiberfil.sys file should have been removed and gone, if not you can safely delete it.