G-P-M on the wrong track?!

Danny Kukawka danny.kukawka at web.de
Mon Oct 17 04:13:21 PDT 2005


On Sunday 16 October 2005 12:26, Matthias Grimm wrote:
> Divide G-P-M in two parts (projects):
>  part 1: Desktop module which visualize interesting data to the user
>          including configuration dialogs
>  part 2: a power management daemon that do the dirty work, provide data
>          to HAL and receive orders from desktop programs through dbus.
>
> This concept has a lot of advantages:
>  - It won't break with existing power management structures. Migration
>    is possible in small steps,
>  - The user can use the Desktop tools with a power manager he likes,
>  - the new power management daemon will cooperate with all desktops,
>    not only with Gnome,
>  - HAL can fulfill its job straight forward. No foreign code anymore.

This is what we do with powersave [1] on SUSE and ALT Linux. There is a 
(desktop and arch (ix86, ix86_64, ia64 and now also ppc) independent) daemon 
which only do powermanagement and which also do powermanagement if there is 
no desktop user logged in. On the other side there are clients (e.g. 
KPowersave/wmpowersave, see e.g. [2]) which communicate with the daemon over 
DBUS to get information, change settings and suspend/standby the machine.

I see also the problem with currently unclear concept of HAL and to build 
blackhole-'mega-system-do-everything daemon' (as I sad in different 
discussions before). We should not workaround all problems for broken 
hardware in HAL (e.g. we should not at special workarounds for broken ACPI 
bios as for COMPAQ EVO N160), this is to much and IMO a problem to maintain. 
Do such things in the kernel or in other ways. 

On the other side, there are also some issues which make IMO sense to set 
devices with HAL where it not make sense to develop a additonal daemon.

In case of powermanagement and ACPI (and also for input abstaction, see IAL), 
I think it make sense to have a (or more different, what ever the 
user/distibutor want) special daemon which only do powermanagement issues 
(and maybe read informations from HAL about hardware, as we do with 
powersave). In this daemon you can concentrate on all related problems and 
workaround problems on a better way than HAL.

I agree your comments.

Cheers,

Danny

[1] http://sourceforge.net/projects/powersave/
[2] http://freshmeat.net/projects/kpowersave


More information about the hal mailing list