Request for feedback and/or participation on https://fedoraproject.org/wiki/Features/PowerManagement

[Eric Sandeen]

Phil Knirsch wrote:
> Bill Nottingham wrote:
>> Phil Knirsch (pknirsch at redhat.com) said: 
>>> In case you're interested in helping make power management better in F11  
>>>  feel free to participate in any form.
>> I'd really like to find a way to get all the things listed in Documentation
>> set up automatically for the user where appropriate - we should have
>> all this stuff by default.
>>
>> Bill
>>
> 
> Thats a good point Bill.
> 
> Of course most of the first points are things that the user just needs 
> to do himself (power off his machine, choose the right dimension for the 
> work he's doing etc).
> 
>  From the pure system ones i know that we at least already use the 
> ondemand by default as soon as the CPU supports it, so we should be fine 
> there.
> 
> Network card speeds and harddisk spindowns is a bit tricker imo, though 
> we probably could enable a higher powersave mode for harddisk by default 
> at least in case a user wants to save power. Some of this is/will be 
> addressed by the tuned i'm working on which monitors the usage of 
> network and harddisk devices and dynamically adapts the settings to the 
> current use.

See also:
[Bug 454582] Tracker bug for over-eager apps that won't let disks spin down

there are still some open bugs under that:

Bug 454574 - mono writing to filesystem far too frequently
Bug 457155 - Tomboy wakes up hard disk frecuently
Bug 466601 - wpa_supplicant writing pointless(?) messages to log every 60s
Bug 479192 - audit log written whenever cron wakes up, keeps disks spun up

> Laptop mode and a higher value for dirty_writeback_centisecs, there i'm 
> personally torn a bit myself. I personally do use it on all my machines 
> (laptop and desktop), but i can understand people who are a bit paranoid 
> about their data integrity not wanting to have that by default. But i'd 
> personally be all for going that way.
> 
> In regard to relatime from what i've found so far we seem to be doing 
> that already by default it seems, though i'd like to have that verified.
> 
> Then disabling CD-ROM polling is definitely something for the ServerSIG, 
> but on a default Desktop i think the user experience would suffer if we 
> would do that by default.
> 
> Enabling USB autosuspend looks like a good candidate for being a default 
> though. I've used it on quite a few Fedora 10 machines around here and 
> haven't experienced any problems so far, so it seems to have matured 
> enough by now from what i can see.
> 
> Last but not least the dpms off, i think that should definitely be part 
> of the Desktop screensaver defaults, especially if you look at how much 
> power a modern LCD display eats when it's only dimmed down to black.

Another one I'll add is powersave for audio hardware; I'll change the
kernel default now (meant to do that last week and wandered off some
other shiny thing instead).  There's some fear that it may cause
clicks/pops on some hardware but we can get it in now and find out.

-Eric