I’m one of those people who hates having to shutdown machines, then restart them, and start logging into all my sites all over again, so I’m particularly thankful for hibernation functionality.
On Ubuntu (possibly Debian as well, but I haven’t checked), you can install either (or both) of the hibernate package, or the TuxOnIce-enabled kernel.
Hibernate is a script that detects whether or not you have a TOI-enabled kernel, and if you have such a kernel, it will use the TOI routines.
Hibernate worked perfectly for me, until I started using BOINC. Then, hibernation would hang with my laptop in a “limbo” state. Neither fully on, nor fully powered off. Turns out that BOINC must be either hogging the memory, or not releasing it properly. So, instead of doing
I do this
sudo service boinc-client stop
sudo hibernate -k
sudo service boinc-client start
So I stop the BOINC service (freeing up memory and CPU cycles), then I do the hibernate (allowing it to kill processes if needed), and then I startup the BOINC service again. The last line only gets executed upon resuming.