On Mon, Jan 9, 2017 at 10:01 AM, David Wright <
deblis@lionunicorn.co.uk> wrote:
> On Sun 08 Jan 2017 at 07:59:39 (+0100), solitone wrote:
>> On Saturday, January 7, 2017 1:35:07 PM CET David Wright wrote:
>> > you could go on to combine it with the
>> > hibernation process to make sure that the monitor was on just before
>> > hibernation started. (There might be some sort of serialisation
>> > required to make sure the two actions occur in the right order. You
>> > don't want a race.)
>>
>> What sort of serialisation are you referring to? I tried with the following
>> script, but won't work:
>>
>> $cat /usr/lib/systemd/system-sleep/screen_hack_hibernate
>>
>> if [ "$2" = "hibernate" ]; then
>> case "$1" in
>> pre)
>> xset -display :0 dpms force on
>> ;;
>> esac
>> fi
>>
>> I thought it would be run just before hibernate (it's the same technique I use
>> to unload the driver of my wifi adapter before hibernate, to prevent some other
>> network issues I had) , but it doesn't.
>
> I can only answer you in the vaguest terms. I thought you might add a
> service that has to run before hibernate, and it would contain a
> Before= (or hibernate an After= ) line to make sure that turning on
> the monitor preceeded the hibernation.
>
> If you manage this, perhaps with others' help, you'll be ahead of me
> on the systemd learning curve.
>
> BTW I haven't bothered to respond to Stefan Monnier's contribution.
> I can imagine scenarios that might cause power consumption when a
> machine is off (like network cards running to watch for magic WoL
> packets, and things like that),
Cheap power supply designs. I think he indicated.
Without load, some power supply designs draw more energy, either in not-fully-defined operating modes or in modes where the P/S loads itself down dynamically.
> but a machine in hibernation should
> cope with a power cut. In any case, I support your expectation that
> using sleep/hibernate should not involve compromising monitors'
> power-saving behaviour.
>
> Cheers,
> David.
>
--
Joel Rees
I'm imagining I'm a novelist:
http://reiisi.blogspot.jp/p/novels-i-am-writing.html