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Sridhar Dhanapalan | 1 Feb 2012 03:45
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Impacts of disabling Automatic Power Management

We are considering disabling Automatic Power Management because of its
impact on collaboration and 3G connectivity.

What kind of battery life can we expect from an XO-1.5 with Automatic
Power Management disabled as opposed to enabled? I understand that
this can vary wildly with usage, but is there an average estimate?

Thanks,
Sridhar

Sridhar Dhanapalan
Engineering Manager
One Laptop per Child Australia
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Sridhar Dhanapalan | 1 Feb 2012 04:37
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Re: [IAEP] [x-post] GNU Project renews focus on free software in education

Brilliant!

What can we do to have Sugar more formally recognised by the FSF? I
think it should be their desktop of choice for primary school
education.

Sridhar

Sridhar Dhanapalan
Engineering Manager
One Laptop per Child Australia

On 31 January 2012 23:28, Anish Mangal <anish <at> activitycentral.com> wrote:
> Hi,
>
> Just received a message on the fsf-info list about FSF relaunching the
> GNU education project:
>
> Links:
> [1] http://www.fsf.org/blogs/community/gnu-education-website-relaunch
> [blog post]
> [2] http://www.gnu.org/education/ [GNU Education website]
>
> --
> Anish
>
>
> * * *
>
>
(Continue reading)

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Paul Fox | 1 Feb 2012 05:43
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Re: Impacts of disabling Automatic Power Management

sridhar wrote:
 > We are considering disabling Automatic Power Management because of its
 > impact on collaboration and 3G connectivity.
 > 
 > What kind of battery life can we expect from an XO-1.5 with Automatic
 > Power Management disabled as opposed to enabled? I understand that
 > this can vary wildly with usage, but is there an average estimate?

he's on a very long plane flight, but i'll try and channel richard:

    "it depends."

how did i do?  :-)

you're probably in as good a position to answer this as we are, since
you have a better idea of your system activity load.  with automatic
power management turned off, a 1.5 is good for several hours of use,
where "several" is intentionally vague.  backlight on full?  wireless
on?  continuous cpu activity?  etc.

would it help to disable automatic power management only when specific
Activities are running?  only when certain kinds of collaboration are
in effect?  only when certain drivers are active?

paul

 > 
 > Thanks,
 > Sridhar
 >
(Continue reading)

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Sridhar Dhanapalan | 1 Feb 2012 05:58
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Re: Impacts of disabling Automatic Power Management

On 1 February 2012 15:43, Paul Fox <pgf <at> laptop.org> wrote:
> sridhar wrote:
>  > We are considering disabling Automatic Power Management because of its
>  > impact on collaboration and 3G connectivity.
>  >
>  > What kind of battery life can we expect from an XO-1.5 with Automatic
>  > Power Management disabled as opposed to enabled? I understand that
>  > this can vary wildly with usage, but is there an average estimate?
>
> he's on a very long plane flight, but i'll try and channel richard:
>
>    "it depends."
>
> how did i do?  :-)

I was trying to head that off with my "I understand that..." statement :)

> you're probably in as good a position to answer this as we are, since
> you have a better idea of your system activity load.  with automatic
> power management turned off, a 1.5 is good for several hours of use,
> where "several" is intentionally vague.  backlight on full?  wireless
> on?  continuous cpu activity?  etc.
>
> would it help to disable automatic power management only when specific
> Activities are running?  only when certain kinds of collaboration are
> in effect?  only when certain drivers are active?

We've been thinking of doing this for when 3G connections are active
[1]. It might be interesting to also tie this into Sugar's
collaboration mechanism and disable power management when a session is
(Continue reading)

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Gary Martin | 1 Feb 2012 06:09

Re: Impacts of disabling Automatic Power Management

On 1 Feb 2012, at 04:43, Paul Fox wrote:

> sridhar wrote:
>> We are considering disabling Automatic Power Management because of its
>> impact on collaboration and 3G connectivity.
>> 
>> What kind of battery life can we expect from an XO-1.5 with Automatic
>> Power Management disabled as opposed to enabled? I understand that
>> this can vary wildly with usage, but is there an average estimate?
> 
> he's on a very long plane flight, but i'll try and channel richard:
> 
>    "it depends."
> 
> how did i do?  :-)
> 
> you're probably in as good a position to answer this as we are, since
> you have a better idea of your system activity load.  with automatic
> power management turned off, a 1.5 is good for several hours of use,
> where "several" is intentionally vague.  backlight on full?  wireless
> on?  continuous cpu activity?  etc.
> 
> would it help to disable automatic power management only when specific
> Activities are running?  only when certain kinds of collaboration are
> in effect?  only when certain drivers are active?

Thanks Paul, yes excellent point. With my Activity Team hat on, Sridhar if you could please expand a little
on the test cases you are hitting Activity collaboration issues with, so that we can try and resolve or
minimise issue from Automatic Power Management kicking in. There are already a number of Activities that
programatically keep the machine awake – a simple example is Clock, who wants the clock display to
(Continue reading)

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Wei-Heng Lin (林蔚恆 | 1 Feb 2012 12:06
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RE: 11.3.1 development build 26 for XO-1.75

Hi Martin,
We have 13 machines passed the 24 hours runin test with OS26.
10 are 4G SKU and the others are 8G.

Still have 3 8G machines doing the runin test.

We confirmed this version fixed many issues as below:
#11392, #11528, #11576, #11546, #11595, #11536, #10831, #10893, #11496, #11321

Will keep update the test results to you.

Best Regards,
－－－－－－－－－－－－－－－
WeiHeng Lin 林蔚恆
Notebook Business Unit 2
Software Design Division
E-mail: weiheng.lin <at> quantatw.com
TEL:886-3-3272345 ext:13313
－－－－－－－－－－－－－－－

-----Original Message-----
From: martin.langhoff.olpc <at> gmail.com [mailto:martin.langhoff.olpc <at> gmail.com] On Behalf Of Martin Langhoff
Sent: Tuesday, January 31, 2012 2:37 AM
To: OLPC Tech Team; Wei-Heng Lin (林蔚恆); Chia-Hsiu Chang (張嘉修); Eddie Tsai ( 蔡豐吉 ); Mars
Chang(張嘉文); Devel List
Subject: 11.3.1 development build 26 for XO-1.75

This build merges kernel 3.0.17 (which reworks the MMC layer), and includes fixes in EC communication,
audio recording & playback, WLAN during suspend/resume and serial port driver. It also downgrades some
graphics libraries back to OS24 versions.
(Continue reading)

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Paul Fox | 1 Feb 2012 17:18
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Re: Impacts of disabling Automatic Power Management

sridhar wrote:
 > On 1 February 2012 15:43, Paul Fox <pgf <at> laptop.org> wrote:
 > > sridhar wrote:
 > >  > We are considering disabling Automatic Power Management because of its
 > >  > impact on collaboration and 3G connectivity.
 > >  >
 > >  > What kind of battery life can we expect from an XO-1.5 with Automatic
 > >  > Power Management disabled as opposed to enabled? I understand that
 > >  > this can vary wildly with usage, but is there an average estimate?
 > >
 > > he's on a very long plane flight, but i'll try and channel richard:
 > >
 > >    "it depends."
 > >
 > > how did i do?  :-)
 > 
 > I was trying to head that off with my "I understand that..." statement :)
 > 
 > 
 > > you're probably in as good a position to answer this as we are, since
 > > you have a better idea of your system activity load.  with automatic
 > > power management turned off, a 1.5 is good for several hours of use,
 > > where "several" is intentionally vague.  backlight on full?  wireless
 > > on?  continuous cpu activity?  etc.
 > >
 > > would it help to disable automatic power management only when specific
 > > Activities are running?  only when certain kinds of collaboration are
 > > in effect?  only when certain drivers are active?
 > 
 > We've been thinking of doing this for when 3G connections are active
(Continue reading)

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Richard A. Smith | 1 Feb 2012 23:09
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Re: Impacts of disabling Automatic Power Management

On 01/31/2012 11:43 PM, Paul Fox wrote:
> sridhar wrote:
>   >  We are considering disabling Automatic Power Management because of its
>   >  impact on collaboration and 3G connectivity.
>   >
>   >  What kind of battery life can we expect from an XO-1.5 with Automatic
>   >  Power Management disabled as opposed to enabled? I understand that
>   >  this can vary wildly with usage, but is there an average estimate?
>
> he's on a very long plane flight, but i'll try and channel richard:
>
>      "it depends."
>
> how did i do?  :-)

You have learned well.

Sirdhar:  Unfortunately theres no way we can answer your question ( or 
even make a SWAG) without known how much idleness is in your normal 
workload.  Automatic Power Management only makes a big difference if 
there is a lot of time spent idle.  If you are running Tam-Tam the 
entire time then turning off aggressive suspend/resume will make zero 
difference.

powerd tracks this though so if you can collect some powerd logs from 
some of your users then we can make a guess at figuring out what your 
impact will be.

powerd logs are located in the ~olcp/power-logs directory.  Copy all the 
files in there off of several machines that have been used in the
(Continue reading)

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Sridhar Dhanapalan | 2 Feb 2012 00:08
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Re: Impacts of disabling Automatic Power Management

On 1 February 2012 16:09, Gary Martin <garycmartin <at> googlemail.com> wrote:
> On 1 Feb 2012, at 04:43, Paul Fox wrote:
>> would it help to disable automatic power management only when specific
>> Activities are running?  only when certain kinds of collaboration are
>> in effect?  only when certain drivers are active?
>
> Thanks Paul, yes excellent point. With my Activity Team hat on, Sridhar if you could please expand a little
on the test cases you are hitting Activity collaboration issues with, so that we can try and resolve or
minimise issue from Automatic Power Management kicking in. There are already a number of Activities that
programatically keep the machine awake – a simple example is Clock, who wants the clock display to
continuously keep stopping as if there's sand stuck in the gears ;)

We've found it really difficult to diagnose and replicate reliably -
the problems can be random. I made an OLPC bug report [1], which is
also in our tracker [2]. The workaround for us (and several other
deployments, I hear) is to disable automatic power management.

I didn't realise that activities could suspend power management. How
does this work, and which activities use it? We see problems with just
about any activity that engages in collaboration. Maybe it should be
standard to suspend power management for any collaboration session?
That would be smarter than turning it off entirely.

Sridhar

[1] http://dev.laptop.org/ticket/10878
[2] https://dev.laptop.org.au/issues/636
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Martin Langhoff | 2 Feb 2012 02:32
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Re: Impacts of disabling Automatic Power Management

On Wed, Feb 1, 2012 at 6:08 PM, Sridhar Dhanapalan
<sridhar <at> laptop.org.au> wrote:
> Maybe it should be
> standard to suspend power management for any collaboration session?
> That would be smarter than turning it off entirely.

I'd be supportive of a patch that does that.

Simon, given the collaboration API in 11.2.x, would it be possible to
keep a file in existence all the while that a collaboration session
exists?

cheers,

m
--

-- 
 martin.langhoff <at> gmail.com
 martin <at> laptop.org -- Software Architect - OLPC
 - ask interesting questions
 - don't get distracted with shiny stuff  - working code first
 - http://wiki.laptop.org/go/User:Martinlanghoff
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Gmane