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What do you think about saving all the RAM memory in a file before the shutdown of the computer and load it in the next boot? With this method you can save the state of your computer, with all the applications running... Is it a stupid idea?

Hi,



It's called "hibernate"...


Cheers,

Brendan

Wow! So it's not a stupid idea...

Hi,



Hehe - Microsoft thinks it's a good idea.

I'm not so sure - I think Microsoft likes it because their OS initialization is far too slow, so recycling everything (including most of the OS initialization) from the previous boot speeds it up heaps (and not needing to re-open applications, etc was an accident).


Cheers,

Brendan

@OP: Remember that if there is a memory leak or something was about to crash, that will also be carried forward to the next session - unless your OS is "memory leak proof"

Cheers,
Adam

Yes, you're right. So for Windows the hibernate function isn't a good thing... Windows is about to crash starting from the bootloader

Somehow though my hibernate button worked in windows a few years ago, now it has been disabled by windows... Can't find the reason.. Tried reinstalling windows.. I have not changed my hardware also...

Hi,

In some versions of windows, you have to specifically enable this. See Control Panel -> Power Options -> Hibernate -> Enable Hibernation.

Cheers,
Adam

I have found that running Disk Cleanup (cleanmgr) and deleting the temporary hibernation file (which I did in an effort to save some space needed for grabbing files at a LAN party) turns off hibernation. Doing what AJ suggests turns it back on again.

I use hibernate all the time on my laptop since my desktop is messy and vista's time from login to usability is about 3 minutes. And this is a really good computer.

If you have a configuration file designed and a FAT12 (or 16 or 32) driver that can save files, you can write the OS up to save the RAM onto disk, set the config file to "yes, boot from the hiberfile next time please!" and write the bootloader to do the loading!

I think it's similar to hibernating, but it can't be done as you describe it. The moment you "hibernate", there may be network connections or devices connected to the PC, applications that have to deal with time, etc. All those could get corrupted. Sure, closing all network connections first could be done. But if you start unmounting devices, closing network devices and even closing applications, we're getting close to normal shut down.

EDIT: think that if you have to unmount a USB drive, you have to close all applications that use that specific USB drive.

Well a lot of those issues apps have to deal with anyway. An app would normally not be put to sleep for three days while running - but under a pre-emptive multi-tasking (non-realtime) OS programs basically have to cope with whatever time slices they get - as well as any delays in between...

The open network connections essentially come back closed after the resume - network apps always need to be prepared for the fundamentally inherent nature of their connection, so if nothing else they should recognize they've lost the link...

As for apps accessing files on a removable drive (or a non-removable drive, for that matter...) - presumably the apps would be shut down before the filesystem is unmounted. How much you do to safeguard those apps from various scenarios (like swapping the drive for another one, etc.) is I guess up to the designer to decide...

some one told me that hidernation can cause your hard drive to screw up. Plus the up side it loads the os much faster

That's absolutely not true. It's just writing a chunk of data on the hard drive. It's as risky as installing programs or copying files.