Hibernating Ubuntu

I’ve had Ubuntu on my laptop for a while, and it nev­er hibern­ated. I’d do what looked like the right things, but it just did­n’t work. So a couple of days ago I decided I should try to track down the prob­lem. I was par­tially suc­cess­ful; hibern­at­ing a laptop prop­erly seems to be dif­fi­cult. Here’s what I did to track down (some of) the problem.

When it comes back after fail­ing to hibern­ate, the sys­tem politely tells you to check the help file for com­mon prob­lems. So you bring up the help file and it con­tains a defin­i­tion of hibern­ate, with no hints as to what might be going wrong, but a point­er to the Ubuntu sup­port for­ums as well as to laptop test­ing pages which sup­posedly con­tain ideas of what to try. The laptop test­ing page claims that hibern­ate works for the Toshiba Tecra M2 that I have, so that did­n’t help much.

Watch­ing closely the next time I tried hibern­at­ing revealed an error mes­sage flash­ing by about not enough swap space. Search­ing for this reveals that the swap space the installer gives you by default may not be enough to man­age hiberna­tion. You need the same size swap as RAM, which I did­n’t have. OK, out with the gpar­ted livecd to recon­fig­ure my par­ti­tions. For­tu­nately I had some spare unused room next to the swap par­ti­tion to grow it into. The next error mes­sage I saw flash­ing by on hibern­at­ing (read­ing it involved hibern­at­ing mul­tiple times, star­ing fix­edly at the right point in the screen, hop­ing that the last mes­sage I saw might be of some use; why can­’t these error mes­sages by default be put in a nice error dia­log box so I can actu­ally read them?) was that the sys­tem could­n’t find the swap space. Pok­ing around the Ubuntu sup­port for­um reveals that each time the machine is rebooted, the swap par­ti­tion gets a new UUID, thereby killing the con­fig files for any scripts that were set up to use the old one. More details here; fol­low­ing the steps in that post­ing finally made hibern­ate mostly work, albeit with a ton of error mes­sages about the USB device (the mouse, I pre­sume, since that’s the only USB device I have con­nec­ted) which I’m ignor­ing. The mostly refers to the fact that the sys­tem often won’t actu­ally come back to life after being in hiberna­tion until I hit the power but­ton and restart from scratch. I have yet to fig­ure out what’s going on there; any hints are welcome.