Page 1 of 1

Notebook: No suspend when battery is low?

Posted: 24 Apr 2017, 12:08
by Rava
System Port 3.1 x86-64 XFCe

While I was online with my laptop using a free WIFI in town, something quite nasty happened.


The battery got low (approx 2 %), so I paused the current download and told Porteus to switch to suspend, via root terminal and "pm-suspend".


But... it went to suspend, just to awake by itself seconds later, draining the nearly empty even further, me again sending it to suspend, just for the system to get back again, so I put it to rest via "halt".

Since I use "no changes", the /var/log/messages is lost, in the few seconds I had left prior the PC crashing due to empty battery, I did not think of copying the /var/log/messages to my harddisk...

Why did it happen that way?


I presume it also happened once in the past, I was in the public library the next town over, and when it was closing time, I also switched the laptop into suspend.

I use some commands, including a self written script that sets the swap priorities after suspend ended the way I want, e.g. the zram swap with higher priority than the swap partition, and adds all known swaps by itself. Usually Porteus resets all swap with priority=1 after a swapoff during suspend.
These commands include echoing the date and time I switch to suspend, and the date & time the PC wakes up again from suspend.

So, by doing so, when I was back home I realized that for some reason the laptop started beeping (as in: battery low), so I gave it mains current.
So I realized it was switched on, and it did switch itself on mere 5 minutes after I put it into suspend, me wondering why it did so. Maybe it also did switched on again back then due to low battery...

In my book, that behaviour makes not much sense. Sure, there can be a warning prior going into suspend that the time is limited the PC can stay in suspend. But waking up again sure drains more battery power than staying in suspend...

Your thoughts? How is that behaviour coded into the system? And how can that behaviour be changed?