G-P-M on the wrong track?!

Matthias Grimm matthiasgrimm at users.sourceforge.net
Sun Oct 16 03:26:50 PDT 2005

Richard might not like to hear this but I think the G-P-M development
is on the wrong track. It started with the aim to build a GUI for power
management features. So far so good. But in the meantime it piles more
and more power management functions and because it runs with user
privileges and need someone to do the dirty work, clutters HAL with low
level power management functions which it is not designed for.

Continuing this path will cause a dilemma for the end user: He has to
decide between a well working power management (for example on powerpc
machines, see pbbuttons.sourceforge.net) and the gnome desktop, because
G-P-M has the GUI he or she likes but the functionallity breaks all
other power management concepts (daemons).

I would like to suggest a slightly change of project aims:

1. HAL
The HAL specifications tells that HAL provides a view and detailed
metadata to attached hardware, not more. Not a word about building the
mega-system-do-everything daemon.

Please return to this aim. Limit HAL's functionallity to collect data
from various sources and provide it to the desktop for visualisation.
According to the specification it is not HAL's task to actively control
certain hardware or start scripts because of desktop programs wanted so.

2. G-P-M (Desktop Part)
The G-P-M project description on gnomefiles.org sais: "The main focus
here is the user interface; e.g. allowing configuration of power
management from the desktop in a sane way"

This is exactly what G-P-M on the Desktop should do. Visualize data
provided by HAL and comunicate with a power management daemon through
dbus, but don't perform any power management functions by itself.

3. The Power Management Daemon
Power management is too critical to lay it in user's hands. It is an
important system feature and must be handled by a system daemon running
with high privileges. No desktop program is able to fulfil this task.

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.

There are sill a lot of questions to answer but I think this concept is
future proof and bring power management on Linux a step forward. There
are a lot of good ideas in G-P-M and a lot of highly motivated and
entusiastic people push it forward with breathtaking speed but it seems
to me that the big plan is incomplete or missing at all. Also everything
is eyed through the Gnome spectacles only but power management is not a
Gnome only issue.

I have developed pbbuttons (power management daemon for Linus on Apple
computers) for four years now and I would be pleased to join the team
developing the new power management daemon I described above.

I'm awaiting your feedback.

 Best Regards

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