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I'm new to ubuntu, was previously using XP on a T60 laptop.

Under XP the hibernate (sleep on disk) and suspend (sleep in ram) functions were working great. When I switched to ubuntu I was informed that hibernate wasn't activated by default due to motherboards not handling it properly. I believe I'm not in this case since it works great with XP.

I've tried hibernate without modifying any configuration file, just using as suggested the CL command

sudo pm-hibernate

It works somehow: from time to time it works normally, but most of the time here is what happens:

  • hibernates correctly after the CL command is issued
  • starts resuming when powered on but stops with a black screen

However I've found a workaround to complete the resume:

  • while the black screen is displayed, just use Fn-F12 (which by default is suspend)
  • resume from suspend by pressing Fn again. The login screen appears.

It worked anytime so far.

To sum up, sometime hibernating from the CL doesn't fully resume, but if we do a blind suspend and resume from suspend, then the computer is restored as it was before hibernating.

I wonder how can suspend work with XP and not with ubuntu on the same computer.

Is this a bug (I'd be happy to file a bug if it helps) ? Can anybody points me to some related online documentation ?

My computer: thinkpad T60 with dual core T2400

EDIT: as explained the comuter may get out of the black screen if a suspend-resume is done on the black screen. I tried to see if ubuntu was reading the keyboard during the black screen, before the suspend-resume... it does! but I'm even more stunned...

If I type blindly "dir" at the black screen level, then when the resume is completed with the workaround mentioned above, and after I've logged in, then I see the result of the dir command in the console I've used to type the pm-hibernate command.

What it seems to mean is that ubuntu is accepting commands before the login has occurred. Seems to be a big security issue...

share|improve this question
Does suspend - resume work as expected? – guntbert Jan 5 '13 at 17:43
Yes that works also with closing the lid and reopening it. – mins Jan 6 '13 at 17:18

For suspend-to-disk (=hibernate) to reliably work you need a swap-partition at least the size of your RAM.
To be honest I never hibernate my T60, I always use suspend to RAM

This becomes even less of a real answer - but as you asked for a bug report I want to point you to, especially the parts further down.

(Remark: I remember problems on my T60 too but I have no idea how I solved them and I don't want to play with settings...)

share|improve this answer
I've more than required swap space on a dedicated partition. Suspend to RAM is ok until the battery load is exhausted isn't it? I have seen that ubuntu is able to use a mixed mode: suspend to RAM and save the data to disk, so that if something happens (battery empty of unexpected power off), then the computer is still able to resume from disk. This is how Windows 7 works by default. I plan to use that also, but when my hibernating issue will be solved. – mins Jan 6 '13 at 17:06
Thanks guntbert for the link to the bug confirmation page. – mins Jan 6 '13 at 19:23

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