Debian Power Management is Weird

The first item on my list of “unexpected problems switching to Linux” has to do with power management, which manifests in two ways.

On my Zenbook, Debian doesn’t put the device to sleep. At least not properly. It’s dead on the regular, even after say only an overnight off the charger (and when the battery was well over 50% the evening before). My Chromebook can last a week or more in sleep mode, and the same Zenbook running Windows behaves as expected. So I don’t understand this problem, nor can I troubleshoot effectively; I can’t determine what conditions cause the failure to sleep vs. not. I assume it’s hardware related, but then all the other hardware seems to operate properly (eg., screen brightness, keyboard backlight, volume control, etc. — all the things that I’d think more likely to be proprietary and thus more likely to have poor hardware support.)

The other problem occurs on all my Debian devices. I set my machines to put the screen to sleep (at say 15m nonuse) before the device itself sleeps (at say 30m). The resulting behavior is that the device wakes the screen to show a notification of the impending sleep mode on the device itself. This makes no sense, but it’s so obvious and recurrent I can’t believe it’s a bug.

I need to look into both issues, and will update this post once I have some answers. Both are annoying but not mission critical, so not high priority at this point.