What is hiberfil.sys, what is its function, how you can delete it and free up disk space on you Windows computer?! Read our comprehensive article below and learn the answers to all these questions. This article applies to Windows 8, Windows 7, Windows Vista and Windows XP.
What is hiberfil.sys?
Windows has two power management modes that you can select from: A Sleep Mode and a Hibernate Mode. The Sleep Mode keeps the computer running in a low power mode, allowing you instantly get back to its working condition, provided power has not failed in the meantime. The Hibernate Mode writes the memory state to the hard disk drive and powers the machine down entirely. This allows you to keep the working state preserved indefinitely and get it back even after a power failure or battery removal.
The Hibernate Mode saves the memory state to a file named hiberfil.sys, which is stored on the hard disk. Since the entire contents of the RAM are written, this file is as big as the amount of RAM your computer has. At the same time, if you have never hibernated your computer, this file will not exist on your hard disk. However, if you have entered the hibernate mode even once, this file will be created and occupy a huge chunk of your hard disk, the size being as much as your RAM.
How to delete hiberfil.sys?
You cannot delete this file directly, since this is a system file managed by Windows. The only way to get rid of this file is to tell Windows never to enter the hibernate mode. For different Windows OSs, the method of achieving this varies, as you will see.
Removing hiberfil.sys in Windows 8
Step 1: Understanding Hibernation in Windows 8.
Windows 8, unlike its predecessors makes extensive use of the hibernation mode, since it makes use of multiple cores in the processor and uses this mode to hibernate some of the non-used cores to conserve power. Thus, Windows 8 does not deem it necessary to completely shut down and reboot the kernel session every time. Instead, it hibernates the kernel session and shuts down the user sessions instead.
Still if you would like to get rid of the hibernation sessions, including the file hiberfil.sys, proceed as follows.
Step 2: Change Windows 8 Power Options.
Go to Control Panel; enter into Hardware and Sound, then into Power Options.
In case some settings are greyed out, they can be selected through Change settings that are currently unavailable. This is where you decide what happens when you close the lid of your laptop.
Step 3: Tell Windows not to enter Hibernate mode.
Un-tick Enable Hybrid Boot and Show Hibernate.
Removing hiberfil.sys in Windows 7 and Windows Vista
The file hiberfil.sys functions in much the same way in Windows 7 and Vista as it does in Windows 8. Only, the extent of use of the Hibernate Mode is left to the user to select and use.
Disable Hibernate mode and delete hiberfil.sys.
Click Start and right-click on the Command Prompt icon and click Run as Administrator.
In the Command Prompt window, type the following command -
powercfg -h off
You will now notice that the Hibernate option is now removed from the Shut Down menu and the hiberfil.sys file is deleted.
Disabling Hibernate Mode in Windows XP
Go to Control Panel, then Power Options and find the Hibernate tab, un-tick the Enable Hibernation box.
Click on Apply and then Ok.
Reboot your PC and manually delete the hiberfil.sys file.
This concludes the article. You should now be familiar with what the hiberfil.sys file is and how to delete hiberfil.sys file in Windows XP, Vista, 7 and 8.