Power management in F10

[Richard Hughes]

On Sat, 2008-11-29 at 14:04 +0100, Tore Anderson wrote:
> Many settings are not adjusted when (dis)connecting mains:
> - /proc/sys/vm/laptop_mode
> - /sys/class/scsi_host/host*/link_power_management_policy
> - /sys/class/net/wlan0/device/tx_power
> - Hard drive APM (hdparm -B)
> - Various tricks to prevent waking hard drive too often:
>   - Increasing dirty_writeback_centisecs and readahead
>   - Remounting file systems with -o relatime

Most of this control belongs in the kernel, and then in userspace we use
something like PMQoS to set a system latency. This is what I'm pushing
for in F11. See
http://blogs.gnome.org/hughsie/2008/11/09/gnome-power-manager-and-devicekit-power/ and http://blogs.gnome.org/hughsie/2008/11/06/devicekit-power-latency-control/

Laptop tools and power.d are userspace hacks that need to go away.

I don't think making the user aware of power settings is a useful thing
to do. I also don't think we should waste power when on AC -- we should
do aggressive power saving even when on AC power as long as this does
not affect desired system latency.

Richard.