Re: A desktop environment[1] kernel wishlist

From: Andy Lutomirski
Date: Thu Oct 30 2014 - 10:53:32 EST


On Thu, Oct 30, 2014 at 7:45 AM, Bastien Nocera <hadess@xxxxxxxxxx> wrote:
> On Wed, 2014-10-29 at 22:16 +0100, Pavel Machek wrote:
>> On Wed 2014-10-29 16:26:16, Theodore Ts'o wrote:
>> > On Wed, Oct 29, 2014 at 12:19:56PM -0700, Andy Lutomirski wrote:
>> > > For a tablet, isn't the relevant piece of information whether the power
>> > > button was recently pressed, not whether the power button caused the wakeup?
>> >
>> > For Android L devices, it has been reported that the device might
>> > power up its screen fully (note I didn't say 'wake up') automatically
>> > when it detects that you are picking it up, or when you double-tap the
>> > screen. It also reportedly has a low power black and white "ambient
>> > display" (ala the Android Wear devics) which allows you to see
>> > notifications without waking up the phone all the way[1]. (All of
>> > this assuming appropriate hardware support, of course.)
>> >
>> > [1] http://www.androidauthority.com/ambient-display-lollipop-541198/
>> >
>> > Which goes back to the concept of having a "suspend" mode is legacy
>> > thinking. Modern devices will soon have not just a "awake" and a
>> > "asleep" modes; there will be (well, is now) a much wider spectrum of
>> > modes, with the goal of using the minimum amount of power while still
>> > providing use functionality to the user.
>>
>> Actually Maemo people (on Nokia N900 and friends) got it right: unlike
>> android devices, it does not suspend to RAM at any point, and still
>> has reasonable battery life.
>
> Android devices don't suspend to RAM. Neither do Tizen devices AFAIK.
>
>> So I agree -- using suspend to RAM on "active" cell phone is just a
>> bad design.
>
> I don't think anyone was discussing cell phones in particular in this
> thread, and knowing when user-space got woken up because of the baseband
> processor having information for us would still be useful.
>

You still haven't addressed what problem this solves that isn't solved
by merely knowing whether the baseband processor has useful
information.

--Andy

--
Andy Lutomirski
AMA Capital Management, LLC
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