Maemo Wiki Mirror - User contributions [en]

Battery Saving

2011-05-17T15:01:15Z

94.174.1.22: /* Powersave bias */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. '''It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.'''

= Before you start =

== Set sensible defaults ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can. You'll want to have had your device for a while, and be familiar with [[Kernel_Power]] and [[DbusScripts]].

== Use the Kernel for Power Users ==

Not just for [[Overclocking]], the [[Kernel_Power]] package helps to save battery power and makes it easy to configure CPU frequency scaling. You should be using this for power saving purposes even if you never choose to go over the stock 600MHz.

=== Enable SmartReflex ===

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and will cause crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, at CPU speeds from 250-805MHz.

=== Undervolted kernel ===

Follow the information on the [[Overclocking]] page, but don't just grab the "ideal" profile and assume it'll be ideal in terms of battery life. If your device is happy and stable on the "starving" profile, with SmartReflex on, then you're onto a winner.

=== Powersave bias ===

The powersave bias setting modifies the behaviour of the ondemand governor to save more power by reducing the target frequency by a specified percentage. This can be used to limit the extent to which the phone will overclock, according to user-specified criteria.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock, basically to underclock the CPU (or at least, undo overclocking it) whilst the device is locked.

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Take IM / e-mail / other connections offline ==

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem. An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required.

The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

So, getting the phone to auto-downgrade to 2G is not hard (scripts to follow).

Slightly harder, though, is getting the phone to upgrade the connection again automatically when we do things that might require 3G. We certainly don't want to change the radio mode every time we unlock the phone, but we can do so on detecting the launch of known 3G applications (again assuming that we're not on a call at the time). However, these applications run within the user session, so you'll need to set up a second instance of DbusScripts running on the session bus in order to process the relevant events.

[[Category:Power users]]

Battery Saving

2011-05-17T14:33:58Z

94.174.1.22: /* Use the Kernel for Power Users */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. '''It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.'''

= Before you start =

== Set sensible defaults ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can. You'll want to have had your device for a while, and be familiar with [[Kernel_Power]] and [[DbusScripts]].

== Use the Kernel for Power Users ==

Not just for [[Overclocking]], the [[Kernel_Power]] package helps to save battery power and makes it easy to configure CPU frequency scaling. You should be using this for power saving purposes even if you never choose to go over the stock 600MHz.

=== Enable SmartReflex ===

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and will cause crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, at CPU speeds from 250-805MHz.

=== Undervolted kernel ===

Follow the information on the [[Overclocking]] page, but don't just grab the "ideal" profile and assume it'll be ideal in terms of battery life. If your device is happy and stable on the "starving" profile, with SmartReflex on, then you're onto a winner.

=== Powersave bias ===

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock, basically to underclock the CPU (or at least, undo overclocking it) whilst the device is locked.

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Take IM / e-mail / other connections offline ==

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem. An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required.

The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

So, getting the phone to auto-downgrade to 2G is not hard (scripts to follow).

Slightly harder, though, is getting the phone to upgrade the connection again automatically when we do things that might require 3G. We certainly don't want to change the radio mode every time we unlock the phone, but we can do so on detecting the launch of known 3G applications (again assuming that we're not on a call at the time). However, these applications run within the user session, so you'll need to set up a second instance of DbusScripts running on the session bus in order to process the relevant events.

[[Category:Power users]]

Battery Saving

2011-05-17T14:27:09Z

94.174.1.22: /* Before you start */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. '''It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.'''

= Before you start =

== Set sensible defaults ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can. You'll want to have had your device for a while, and be familiar with [[Kernel_Power]] and [[DbusScripts]].

== Use the Kernel for Power Users ==

Not just for [[Overclocking]], the [[Kernel_Power]] package helps to save battery power and makes it easy to configure CPU frequency scaling. You should be using this for power saving purposes even if you never choose to go over the stock 600MHz.

=== Enable SmartReflex ===

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and will cause crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, at CPU speeds from 250-805MHz.

=== Undervolted kernel ===

Follow the information on the [[Overclocking]] page, but don't just grab the "ideal" profile and assume it'll be ideal in terms of battery life. If your device is happy and stable on the "starving" profile, with SmartReflex on, then you're onto a winner.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock, basically to underclock the CPU (or at least, undo overclocking it) whilst the device is locked.

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Take IM / e-mail / other connections offline ==

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem. An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required.

The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

So, getting the phone to auto-downgrade to 2G is not hard (scripts to follow).

Slightly harder, though, is getting the phone to upgrade the connection again automatically when we do things that might require 3G. We certainly don't want to change the radio mode every time we unlock the phone, but we can do so on detecting the launch of known 3G applications (again assuming that we're not on a call at the time). However, these applications run within the user session, so you'll need to set up a second instance of DbusScripts running on the session bus in order to process the relevant events.

[[Category:Power users]]

Battery Saving

2011-05-17T14:26:42Z

94.174.1.22: /* Set sensible defaults */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. '''It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.'''

= Before you start =

== Set sensible defaults ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can. You'll want to have had your device for a while, and be familiar with [[Kernel_Power]] and [[DbusScripts]].

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

== Use the Kernel for Power Users ==

Not just for [[Overclocking]], the [[Kernel_Power]] package helps to save battery power and makes it easy to configure CPU frequency scaling. You should be using this for power saving purposes even if you never choose to go over the stock 600MHz.

=== Enable SmartReflex ===

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and will cause crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, at CPU speeds from 250-805MHz.

=== Undervolted kernel ===

Follow the information on the [[Overclocking]] page, but don't just grab the "ideal" profile and assume it'll be ideal in terms of battery life. If your device is happy and stable on the "starving" profile, with SmartReflex on, then you're onto a winner.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock, basically to underclock the CPU (or at least, undo overclocking it) whilst the device is locked.

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Take IM / e-mail / other connections offline ==

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem. An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required.

The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

So, getting the phone to auto-downgrade to 2G is not hard (scripts to follow).

Slightly harder, though, is getting the phone to upgrade the connection again automatically when we do things that might require 3G. We certainly don't want to change the radio mode every time we unlock the phone, but we can do so on detecting the launch of known 3G applications (again assuming that we're not on a call at the time). However, these applications run within the user session, so you'll need to set up a second instance of DbusScripts running on the session bus in order to process the relevant events.

[[Category:Power users]]

Battery Saving

2011-05-17T14:24:33Z

94.174.1.22: /* Enable SmartReflex */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. '''It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.'''

= Before you start =

== Set sensible defaults ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can.

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

== Use the Kernel for Power Users ==

Not just for [[Overclocking]], the [[Kernel_Power]] package helps to save battery power and makes it easy to configure CPU frequency scaling. You should be using this for power saving purposes even if you never choose to go over the stock 600MHz.

=== Enable SmartReflex ===

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and will cause crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, at CPU speeds from 250-805MHz.

=== Undervolted kernel ===

Follow the information on the [[Overclocking]] page, but don't just grab the "ideal" profile and assume it'll be ideal in terms of battery life. If your device is happy and stable on the "starving" profile, with SmartReflex on, then you're onto a winner.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock, basically to underclock the CPU (or at least, undo overclocking it) whilst the device is locked.

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Take IM / e-mail / other connections offline ==

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem. An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required.

The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

So, getting the phone to auto-downgrade to 2G is not hard (scripts to follow).

Slightly harder, though, is getting the phone to upgrade the connection again automatically when we do things that might require 3G. We certainly don't want to change the radio mode every time we unlock the phone, but we can do so on detecting the launch of known 3G applications (again assuming that we're not on a call at the time). However, these applications run within the user session, so you'll need to set up a second instance of DbusScripts running on the session bus in order to process the relevant events.

[[Category:Power users]]

Battery Saving

2011-05-17T14:20:58Z

94.174.1.22: /* Use the Kernel for Power Users */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. '''It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.'''

= Before you start =

== Set sensible defaults ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can.

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

== Use the Kernel for Power Users ==

Not just for [[Overclocking]], the [[Kernel_Power]] package helps to save battery power and makes it easy to configure CPU frequency scaling. You should be using this for power saving purposes even if you never choose to go over the stock 600MHz.

=== Enable SmartReflex ===

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and causes crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, but does not overclock above 805MHz.

=== Undervolted kernel ===

Follow the information on the [[Overclocking]] page, but don't just grab the "ideal" profile and assume it'll be ideal in terms of battery life. If your device is happy and stable on the "starving" profile, with SmartReflex on, then you're onto a winner.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock, basically to underclock the CPU (or at least, undo overclocking it) whilst the device is locked.

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Take IM / e-mail / other connections offline ==

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem. An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required.

The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

So, getting the phone to auto-downgrade to 2G is not hard (scripts to follow).

Slightly harder, though, is getting the phone to upgrade the connection again automatically when we do things that might require 3G. We certainly don't want to change the radio mode every time we unlock the phone, but we can do so on detecting the launch of known 3G applications (again assuming that we're not on a call at the time). However, these applications run within the user session, so you'll need to set up a second instance of DbusScripts running on the session bus in order to process the relevant events.

[[Category:Power users]]

Battery Saving

2011-05-17T14:20:11Z

94.174.1.22: /* Before you start */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. '''It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.'''

= Before you start =

== Set sensible defaults ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can.

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

== Use the Kernel for Power Users ==

Not just for [[Overclocking]], the [[Kernel_power]] package helps to save battery power and makes it easy to configure the kernel. You should be using this for power saving purposes, even if you never choose to go over the stock 600MHz.

=== Enable SmartReflex ===

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and causes crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, but does not overclock above 805MHz.

=== Undervolted kernel ===

Follow the information on the [[Overclocking]] page, but don't just grab the "ideal" profile and assume it'll be ideal in terms of battery life. If your device is happy and stable on the "starving" profile, with SmartReflex on, then you're onto a winner.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock, basically to underclock the CPU (or at least, undo overclocking it) whilst the device is locked.

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Take IM / e-mail / other connections offline ==

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem. An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required.

The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

So, getting the phone to auto-downgrade to 2G is not hard (scripts to follow).

Slightly harder, though, is getting the phone to upgrade the connection again automatically when we do things that might require 3G. We certainly don't want to change the radio mode every time we unlock the phone, but we can do so on detecting the launch of known 3G applications (again assuming that we're not on a call at the time). However, these applications run within the user session, so you'll need to set up a second instance of DbusScripts running on the session bus in order to process the relevant events.

[[Category:Power users]]

Battery Saving

2011-05-17T14:19:30Z

94.174.1.22: /* Before you start */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. '''It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.'''

= Before you start =

== Set sensible defaults ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can.

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

== Use the Kernel for Power Users ==

Not just for [[Overclocking]], the [[Kernel_power]] package helps to save battery power and makes it easy to configure the kernel. You should be using this for power saving purposes, even if you never choose to go over the stock 600MHz.

== Enable SmartReflex ==

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and causes crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, but does not overclock above 805MHz.

== Undervolted kernel ==

Follow the information on the [[Overclocking]] page, but don't just grab the "ideal" profile and assume it'll be ideal in terms of battery life. If your device is happy and stable on the "starving" profile, with SmartReflex on, then you're onto a winner.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock, basically to underclock the CPU (or at least, undo overclocking it) whilst the device is locked.

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Take IM / e-mail / other connections offline ==

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem. An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required.

The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

So, getting the phone to auto-downgrade to 2G is not hard (scripts to follow).

Slightly harder, though, is getting the phone to upgrade the connection again automatically when we do things that might require 3G. We certainly don't want to change the radio mode every time we unlock the phone, but we can do so on detecting the launch of known 3G applications (again assuming that we're not on a call at the time). However, these applications run within the user session, so you'll need to set up a second instance of DbusScripts running on the session bus in order to process the relevant events.

[[Category:Power users]]

Overclocking

2011-05-17T14:11:21Z

94.174.1.22: /* /sys/power/vdd1_opps_vsel values */

==Overclocking==

This page is about overclocking the [[Nokia N900|N900]]. For the N8x0 see [http://talk.maemo.org/showthread.php?t=12464 this thread on talk.maemo.org]

# ''WORK IN PROGRESS, HELP IF YOU WANT''

Overclocking is discussed in [http://talk.maemo.org/showthread.php?t=39753 this thread]. Benchmark results can be found [http://talk.maemo.org/showthread.php?p=605189 here]. If you're more interested in power saving read [http://talk.maemo.org/showthread.php?t=49654 this].

The [[Kernel_Power]] article includes [[Kernel_Power#Basic.2C_Conservative_Undervolting.2Foverclocking|instructions on overclocking with ''kernel-config'']]. You might save yourself time by trying that first.

==Warnings==

* Overclocking WILL VOID YOUR WARRANTY. Your warranty does not cover running the device beyond the specifications.
* The lifetime of your device WILL get reduced (see below)
* Your data might get corrupted (for example, file system corruption)
* Every device is an individual, what is stable for others might not be for you
* If you encounter ANY unusual problems, lower your clock frequency (though it might be too late then, see [[:wikipedia:Electromigration]])
* You do it at your own responsibility. No whining afterwards. If you're unsure, don't do it.
* [http://depot.javispedro.com/nit/thewarningtm.jpeg Nokia's overclocking warning]: 500 MHz is the normal frequency. Everything above is not good for your device, even with the stock kernel.
* Igor Stoppa's [http://talk.maemo.org/showpost.php?p=596149&postcount=904 warning] and [http://talk.maemo.org/showpost.php?p=603833&postcount=66 comment]
* [http://talk.maemo.org/showpost.php?p=596274&postcount=937 chip vendors specs]

==Lifetime, warranty and damage==

* The expected lifetime '''all''' devices is limited due to wear.
* It is usually much longer (several years) than the warranty period, so that even with heavy use within the specifications it would not fail before warranty ends.
* With overclocking users may see considerable speed improvements and lower latency in user experience which could extend the actual lifetime (of being used) as the device could keep up with the newer models.
* Naive overclocking with stock voltages is definitely bad for most components in your device, especially if the device is continuously locked at high frequencies with high load (see TI specs).
* Specifications give guarantees for the worst-case scenarios that are covered by the warranty. The best-case scenario may be different for every device but is not covered by warranty.
* However, there is an open debate whether '''mild''' (<40%) overclocking with lower voltages (undervolting) does actually harm or is even less harmful than the stock settings. See [[#Undervolting and voltage tables]] for an explanation why undervolting in fact won't help anything due to chip using SmartReflex Technology (which can not be disabled).
* Evidence for or against damages (esp. with undervolting) in the N900 is currently absent and will probably only be available when the device is no longer on the market. Or you decide to acquire thorough electronics engineer's understanding of the issue, and study TI's papers regarding SmartReflex™ and how it works - then all the evidence for damage positively done is there already.
* Therefore, if you are unsure and you want to avoid potential damages, do not overclock!

==Overclocking, bugzilla & errors==

* Running a device overclocked for long periods of time could produce unwanted side effects, even persisting ones that won't revert when overclocking is stopped. If you are experiencing errors following Overclocking and intend to report those errors to talk.maemo.org or bugzilla, please consider the following :
** Errors induced by overclocking will not always appear to be as such.
** It will be considered a good idea to reproduce your error / problem on a device which has never been overclocked AT ALL, before proceeding with actions regarding your problem.
** In the event you have decided to file a bug report or open a thread about your problem, please add a note to that report, mentioning that you are or previously were in fact running your device overclocked. Please also provide details about the period and amount of overclocking used.
* The reason for these requirements is that there are many problems pending for developer's attention. It is a huge waste of time to try and trace down an error without knowing all the facts, just to find out in the end that the particular problem was caused by a damaged hardware. If the developers know about it, they can take it into account and won't rule out a 1+1=3 problem on the reporter's device during their analysis.

==Available kernels==

Overclocking requires installation of a custom kernel. There are two types of kernels:
# modified [[Maemo 5/PR1.1|PR1.1]] kernels by Lehto and others. The only difference from the stock Nokia kernel is the change of the available hardcoded frequencies.
# enhanced kernels by titan (highly recommended). They are compatible with [[Maemo 5/PR1.2|PR1.2]] and [[Maemo 5/PR1.3|PR1.3]], contain lots of additional features (IPv6, NAT etc) and bugfixes. In addition they include a large set of possible frequencies (125 MHz-1.15 GHz) which you manually set and try out without flashing a new kernel. The defaults are set to the standard 250-600 MHz range. The kernel can be installed via HAM from the [[extras-testing]] or [[extras-devel]] catalog.

=== Jakiman's Guide to Overclocking for Newcomers ===

[http://talk.maemo.org/showpost.php?p=595582&postcount=774 Jakiman's Overclock Guide / Summary] (constantly updated)

=== Installation of Lehto's PR1.1 kernels ===

[http://talk.maemo.org/showpost.php?p=594200&postcount=309 Lehto's Kernels]
*No longer available* Sorry about that. -Lehto

=== Installation of titan's enhanced kernels ===

This kernel makes it possible to dynamically change the maximum frequency up to 1.15 GHz (supported frequencies are 125, 250, 500, 550, 600, 700, 750, 805, 850, 900, 950, 1000, 1100, 1150 MHz).

see the separate page for this kernel: [[Kernel_Power]]

[http://talk.maemo.org/showthread.php?t=43420 talk.maemo.org: Discussion of the enhanced kernel]

==Additional information and hints==

# the frequencies available in the Nokia kernel are: 250, 500, 550 and 600 MHz.
# the CPU does '''NOT IDLE''' at the lowest frequency (250 MHz) but it '''SLEEPS''' at 0 MHz! Thus, reducing the lowest frequency would not reduce power consumption. It is only activated during low workload and may actually consume more power than a higher frequency, as it takes more time to go back to sleep/idle state.
# setting the lowest frequency to 125 MHz does NOT improve battery life. In fact, many people noticed worse battery life, instability and worse responsiveness,
# Nokia [http://talk.maemo.org/showpost.php?p=601691&postcount=1823 locks the device to 600 MHz] during phone calls. This may be a bug. It also [http://talk.maemo.org/showpost.php?p=600721&postcount=1720 affects] Lehto's kernels.
# the telephone app is closed-source and broken. After a phone call it sets the maximum to 600 Mhz and the minimum to 250 MHz (or 125 MHz if available) irrespective of what you have set before. The are some workarounds in the Kernel-power kernel.
# when connected via USB the device locks the minimum frequency to 500 Mhz.
# By default the device is configured to use 125 MHz as the lowest frequency but it not enabled in the kernel [https://bugs.maemo.org/show_bug.cgi?id=7116 pmconfig bug]
# [http://talk.maemo.org/showpost.php?p=599870&postcount=170 improving responsiveness]
# [http://talk.maemo.org/showpost.php?p=599618&postcount=168 safe pmconfig configuration]
# the warning <pre>WARNING: at arch/arm/mach-omap2/clock34xx.c:443 omap3_noncore_dpll_set_rate+0x28c/0x2dc()</pre> in the kernel logs (dmesg) only happens if the invalid 800 MHz frequency was selected. ignore it.
# [http://talk.maemo.org/showpost.php?p=603585&postcount=189 saving more battery power when idle]
# EvilJazz had photoshopped a [http://talk.maemo.org/showpost.php?p=605523&postcount=90 picture of a device being overclocked 1.7GHz]. It's a '''prank'''!
# reading one of the temperature sensors "cat /sys/devices/platform/omap34xx_temp/temp1_input"

==Useful stuff==

===Show current CPU frequency===

awk '{print $1/1000" MHz"}' /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq

'''Important: this command may cause the CPU to bump up to its highest allowed frequency (in other words, you are likely to only see the highest frequency reported when checking this way).'''

===Set maximum CPU frequency===

From root terminal:

echo "echo 600000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq" | root

Replace 600000 with desired maximum frequency. Pay attention to the two exceptions in titan's kernels (124999 and 599000). The list of available frequencies on your device/kernel can be obtained with command:

awk '{print $1/1000" MHz"}' /sys/devices/system/cpu/cpu0/cpufreq/stats/time_in_state

===Script for analyzing time_in_state (by rooted) - rev7===

''I've stopped the development of this script and I hope someone will make use of the code. I hope titan includes it in "kernel-config show" or "kernel-config debug". -rooted''

This script prints percentage of frequencies (states) used and some additional info useful for posting on the forum (debugging). It displays all frequencies, works with all kernels and it is not affected by the bug which resets minimum frequency after phone call.

Temperature may not be listed if you don't have module bq27x00_battery installed or enabled. Also kernel-power version is not listed if you don't use titan's kernel.

<source lang="bash">
#!/bin/sh

idlefreq=`awk '{if ($2 > 0) print $1}' /sys/devices/system/cpu/cpu0/cpufreq/stats/time_in_state | tail -n 1`
tis1=`awk '{sum += $2} END {print sum}' /sys/devices/system/cpu/cpu0/cpufreq/stats/time_in_state`
tis2=`awk '$1 == "'"$idlefreq"'" {idle = $2} {sum += $2} END {print sum-idle}' /sys/devices/system/cpu/cpu0/cpufreq/stats/time_in_state`

echo -e "
TIME_IN_STATE ANALYSING SCRIPT
By rooted (maemo.org)
Revision 7
wiki.maemo.org/Overclocking

FREQUENCY\tUSED\t\tWHEN BUSY\n"
awk '
{if ($1 >= 1000000) printf ("%.0f MHz\t",$1/1000); else printf ("%.0f MHz\t\t",$1/1000)}
{if ($2 == 0) printf "unused"; else printf ("%.1f %\t\t",($2*100)/"'"$tis1"'")}
{if ($2 == 0 || $2/"'"$tis2"'" > 1) printf "\n"; else printf ("%.1f %\n",($2*100)/"'"$tis2"'")}
' /sys/devices/system/cpu/cpu0/cpufreq/stats/time_in_state

echo -e "
Kernel: `uname -r`
kernel-power: `dpkg -l kernel-power | awk '$2 == "kernel-power" {print $3}'`
kernel-power-settings: `dpkg -l kernel-power-settings | awk '$2 == "kernel-power-settings" {print $3}'`
Uptime: `uptime | sed -e 's/.*p *//' -e 's/, l.*//' -e 's/ / /'`
Load: `uptime | sed 's/.*e: //'`
Boot reason: `cat /proc/bootreason`
Temperature: `cat /sys/class/power_supply/bq27200-0/temp` degrees C\n"
</source>

Output example:

<pre>TIME_IN_STATE ANALYSING SCRIPT
By rooted (maemo.org)
Revision 7
wiki.maemo.org/Overclocking

FREQUENCY USED WHEN BUSY

1150 MHz unused
1100 MHz unused
1000 MHz unused
950 MHz unused
900 MHz unused
850 MHz unused
805 MHz 4.5 % 58.9 %
750 MHz 0.0 % 0.4 %
700 MHz 0.0 % 0.3 %
600 MHz 0.3 % 3.4 %
550 MHz 0.0 % 0.5 %
500 MHz 2.8 % 36.5 %
250 MHz 92.4 %
125 MHz unused

Kernel: 2.6.28.10power37
kernel-power: 2.6.28-maemo37
kernel-power-settings: 0.11
Uptime: 56 min
Load: 0.25, 0.12, 0.09
Boot reason: pwr_key
Temperature: 31 degrees C</pre>

===Analyzing time in state, including idle mode stats (by ArbitRabbit)===

The following script will show the current frequency and statistics for each state, including time spent in idle mode when the CPU is actually sleeping. This script works with the special frequency handling in Titan's kernel.

To run this script as user and be able to set the frequencies you will need to install "[[Root_access|rootsh]]" via apt-get.

'''scheduler_stats.sh'''
<source lang="bash">
#!/bin/sh
awk '{print "\nCurrent frequency: "$1/1000" MHz\n"}' /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
awk '{print "Minimum frequency: "$1/1000" MHz\n"}' /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
awk '{print "Maximum frequency: "$1/1000" MHz\n"}' /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq

tis1=`awk '{SUM += $2} END {printf("%.0f",SUM/1000)}' /sys/devices/system/cpu/cpu0/cpufreq/stats/time_in_state`

idle0=`awk '{printf ("%.0f",$1/1000)}' /sys/devices/system/cpu/cpu0/cpuidle/state0/time`

idle1=`awk '{printf ("%.0f",$1/1000)}' /sys/devices/system/cpu/cpu0/cpuidle/state1/time`

idle2=`awk '{printf ("%.0f",$1/1000)}' /sys/devices/system/cpu/cpu0/cpuidle/state2/time`

idle3=`awk '{printf ("%.0f",$1/1000)}' /sys/devices/system/cpu/cpu0/cpuidle/state3/time`

totaltime=$(($idle0+$idle1+$idle2+$idle3+$tis1))
echo -e "FREQUENCY\tUSED"
SUM=0
awk '
{
printf (($1/1000)" MHz \t");
if ($2 == 0)
{
printf "0 %\n";
}
else {
SUM+=$2;
printf("%.3f %\n",($2/10)/"'"$totaltime"'");
}
}
END{
printf ("Time spent in idle mode is %2.2f %\n",(1-((SUM/1000)/"'"$totaltime"'"))*100);
}' /sys/devices/system/cpu/cpu0/cpufreq/stats/time_in_state
echo ""
</source>

'''Sample Output'''

<pre>Current frequency: 500 MHz

Minimum frequency: 500 MHz

Maximum frequency: 810 MHz

FREQUENCY USED
1200 MHz 0 %
1100 MHz 0 %
1000 MHz 0 %
950 MHz 0 %
900 MHz 0 %
850 MHz 0 %
810 MHz 0.000 %
750 MHz 0.000 %
700 MHz 0.000 %
600 MHz 0.000 %
550 MHz 0.000 %
500 MHz 0.010 %
Time spent in idle mode is 99.99 %</pre>

Known Bugs: Requires the Phone to be booted for an hour or so before it results in decent stats.

===Combined helper script (by evilJazz)===

The following script will show the current frequency and statistics. It also accepts two optional parameters that will set the max and/or min frequencies (in MHz unit). Calling the script without these parameters will not set the new clocking. Instead it will just show the current frequencies and statistics.

This script works with the special frequency handling in Titan's kernel.

To run this script as user and be able to set the frequencies you will need to install "[[Root_access|rootsh]]" via apt-get.

overclock.sh [max freq] [min freq]

<source lang="bash">
#!/bin/sh
max=${1}000
min=${2}000

# Handle and rewrite special cases in Titan's kernel...
[ "$max" == "600000" ] && max=599000
[ "$min" == "125000" ] && min=124999

if [ $(id -u) -ne 0 ]; then
[ "$max" != "000" ] && echo "echo $max > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq" | sudo gainroot
[ "$min" != "000" ] && echo "echo $min > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq" | sudo gainroot
else
[ "$max" != "000" ] && echo $max > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
[ "$min" != "000" ] && echo $min > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
fi

awk '{printf("\nCurrent frequency: %7s MHz\n", $1/1000)}' /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
awk '{printf("Minimal frequency: %7s MHz\n", $1/1000)}' /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
awk '{printf("Maximal frequency: %7s MHz\n\n", $1/1000)}' /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq

sum=$(awk '{SUM += $2} END {print SUM}' /sys/devices/system/cpu/cpu0/cpufreq/stats/time_in_state)
awk '{printf("%7s MHz: %5.1f % (%8d)\n", ($1/1000), ($2 * 100)/"'"$sum"'", $2)}' /sys/devices/system/cpu/cpu0/cpufreq/stats/time_in_state
echo
</source>

Output example:

<pre>~ $ ./overclock.sh 600 250

Current frequency: 250 MHz
Minimal frequency: 250 MHz
Maximal frequency: 599 MHz

1200 MHz: 0.0 % ( 0)
1100 MHz: 0.0 % ( 0)
1000 MHz: 0.0 % ( 0)
950 MHz: 0.0 % ( 0)
900 MHz: 0.2 % ( 271)
850 MHz: 0.0 % ( 0)
810 MHz: 0.0 % ( 0)
750 MHz: 0.0 % ( 0)
700 MHz: 0.0 % ( 0)
600 MHz: 9.0 % ( 13663)
550 MHz: 0.5 % ( 701)
500 MHz: 15.4 % ( 23379)
250 MHz: 75.0 % ( 114021)
124.999 MHz: 0.0 % ( 0)</pre>

===Underclock/Overclock when phone is Locked/Unlocked (by Fecn)===

When locked, the limits are changed to 250/500 Mhz to save power - I don't need my phone to be fast when it's sitting there doing nothing. (I did try with 125 Mhz as minimum but it caused an unresponsive touchscreen during incoming phone calls and alarms)

When unlocked, the limits are set for overclocking, with the max speed determined by the temperature (1150 Mhz is stable on my phone - your mileage may vary - adjust scripts as required)

You need the dbus-scripts package installed for this to work. You also need to add bq27x00_battery to your /etc/modules so that it is loaded at boot time - it needs to be loaded to be able to read the temperature.

Note by --[[User:joerg_rw|joerg_rw]] 18:03, 2 August 2010 (UTC):
Which temperature are you trying to base that on? Anyway the bq27200 temperature is vastly useless for this purpose, as it is the die (chip) temperature of the battery charge gauge, and neither related to CPU die temperature, nor to battery cell temperature.

We use the dbus-signalling to follow what the phone is doing and fire off scripts to change the limits accordingly.

Create the following two 1-line files inside /etc/dbus-scripts.d/ (before you need to install the dbus-scripts package)

<pre>
Filename: /etc/dbus-scripts.d/locked
/usr/local/bin/underclock * * com.nokia.mce.signal tklock_mode_ind locked

Filename: /etc/dbus-scripts.d/unlocked
/usr/local/bin/overclock * * com.nokia.mce.signal tklock_mode_ind unlocked
</pre>

... and then create corresponding scripts that they call inside /usr/local/bin/ ( don't forget to chmod them to executable )

<pre>
Filename: /usr/local/bin/underclock
#!/bin/sh
kernel-config limits 250 500

Filename: /usr/local/bin/overclock
#!/bin/sh
TEMP=`cat /sys/class/power_supply/bq27200-0/temp`
echo "Temp is :" $TEMP "C"
MAXSPEED="1150"
if [ $TEMP -gt "38" ] ; then MAXSPEED="1000" ; fi
if [ $TEMP -gt "40" ] ; then MAXSPEED="950" ; fi
if [ $TEMP -gt "43" ] ; then MAXSPEED="850" ; fi
if [ $TEMP -gt "45" ] ; then MAXSPEED="750" ; fi
if [ $TEMP -gt "47" ] ; then MAXSPEED="600" ; fi
echo "Setting max as :" $MAXSPEED "Mhz"

kernel-config limits 250 $MAXSPEED
</pre>

You'll need to restart dbus-scripts for it to see the new configs. I found that the scripts in init.d weren't too good at doing this, so had to kill it manually each time.

If you want to scale your processor speed according to battery capacity in addition to temperature, use an overclock script something like the following:

<pre>
Filename: /usr/local/bin/overclock
#!/bin/sh
TEMP=`cat /sys/class/power_supply/bq27200-0/temp`
echo "Temp is:" $TEMP "C"
MAXSPEED="1150"
if [ $TEMP -gt "38" ] ; then MAXSPEED="1000" ; fi
if [ $TEMP -gt "40" ] ; then MAXSPEED="950" ; fi
if [ $TEMP -gt "43" ] ; then MAXSPEED="850" ; fi
if [ $TEMP -gt "45" ] ; then MAXSPEED="750" ; fi
if [ $TEMP -gt "47" ] ; then MAXSPEED="600" ; fi

BATTERY=`cat /sys/class/power_supply/bq27200-0/capacity`
echo "Battery is:" $BATTERY "% full"
MAXSPEEDTWO="1150"
if [ $BATTERY -lt "60" ] ; then MAXSPEEDTWO="850" ; fi
if [ $BATTERY -lt "40" ] ; then MAXSPEEDTWO="600" ; fi
if [ $BATTERY -lt "25" ] ; then MAXSPEEDTWO="500" ; fi

if [ $MAXSPEEDTWO -lt $MAXSPEED ] ; then MAXSPEED=$MAXSPEEDTWO ; fi

echo "Setting max as:" $MAXSPEED "Mhz"

kernel-config limits 250 $MAXSPEED
</pre>

==Changing the Kernel==

===Installing a modified Kernel===

====Flashing using PC====

# Power off the N900 completely.
# Hold "u" on the N900's keyboard, while holding, connect it to the PC via USB cable.
# You will see usb icon on top right of white Nokia screen.
# Now you can let go of "u" on the keyboard.
# Now use flasher utility with the kernel file located in the same directory.<pre>flasher-3.5 -k image_file_name -f -R</pre>
# It should take about 1-2 seconds then it'll say Done.
# Now your N900 will show white Nokia screen. (reboot)
# At this time, you can pull out the USB cable.
# N900 should finish booting up if all goes well.
# Test out your phone as usual. (Apps, browser, camera, phone etc etc)
# If any abnormal events occur frequently (crash, hang, screen corruption etc), turn it off, flash it to a slower kernel and test again.
note: For Windows7 64bit users, you may need to use WindowsXP mode. ([http://www.youtube.com/watch?v=Bx6dblXl2eo Youtube Tutorial])

====Flashing from N900 xterminal====

* do a backup, have a PC nearby and know you are able to flash the N900 with flasher-3.5 - just in case

# Launch xterminal app then type sudo gainroot (need rootsh installed)
# Type:<pre>softupd -vv -s --local</pre>(that is a double v)
# Open new terminal
# Type:<pre>flasher --local -f -k <kernel_zimage_file_with_path></pre>
# You'll see the flashing (takes some time)
# Type "sync" to save changes
# Type "reboot" and enter to restart
# Test out your phone as usual. (Apps, browser, camera, phone etc etc)
# If any abnormal events occur frequently (crash, hang, screen corruption etc), turn it off, flash it to a slower kernel and test again.

'''You are fully responsible for any damage caused by overclocking. Not anyone else.'''

===Reverting to the Original Kernel===

If you want to revert to the original kernel, execute:

apt-get install --reinstall kernel kernel-flasher

=== Fixing the version information ===

If your version information got lost (control panel -> version) you can fix it by reinstalling the package that is listed with:
dpkg -l "mp-fremantle*"
for example, "mp-fremantle-generic-pr" (for some firmwares 002 or 003 instead of generic) and then execute:
apt-get install --reinstall mp-fremantle-generic-pr

==Undervolting and voltage tables==

See: http://talk.maemo.org/showpost.php?p=628839&postcount=81

Extract from the post:

<code>CPU power consumption (without constants) = leakage + capacitance + switching = voltage^2 + frequency + (voltage^2 * frequency)</code>

One factor reducing CPU lifetime is the current it is running with.

<code>CPU dynamic power consumption = capacitance * frequency * voltage^2</code> ([[:wikipedia:Dynamic_frequency_scaling]])

As can be seen from the formula, lower voltage plays greater part in CPU consumption than frequency. By reducing the voltage the damage of overclocking can be reduced and the battery life time extended. Alas, this claim only holds true for architectures not regulating the real voltage and current in special on chip regulators, like OMAP is known to do for almost every gate in their CPU and other SoC function blocks. TI calls this feature SmartReflex™ and lowering the voltage applied to the whole SoC, like suggested here, only reduces the voltage drop across these regulators, thus no positive effect on electromigration damage ([[:wikipedia:Electromigration]]) caused by overclocking is to be expected.

===Calculating voltages===

According to [http://talk.maemo.org/showpost.php?p=606031&postcount=2375 this calculations] the voltage can be varied in steps of 0.0125 V with values 0-72. The formula is (with x being the kernel parameter value):

<code>V = x * 0.0125 + 0.6</code>

Examples:

Lowest voltage (x = 0): 0 * 0.0125 + 0.6 = 0 + 0.6 = 0.6 V
Highest voltage (x = 72): 72 * 0.0125 + 0.6 = 0.9 + 0.6 = 1.5 V
Random voltage (x = 38): 38 * 0.0125 + 0.6 = 0.475 + 0.6 = 1.075 V

===Summary===

FREQUENCY Nokia LV ULV XLV ideal
0 MHz 30 30 25 30 30
125 MHz 30 30 25 20 30
250 MHz 38 38 25 30 30
500 MHz 48 48 33 33 30
550 MHz *54* 48 38 38 33
600 MHz 60 *54* 38 38 38
700 MHz 54 45 45 45
750 MHz 54 45 45 45
810 MHz 54 48 48 48
850 MHz 54 48 48 48
900 MHz 54 *54* *54* *54*
950 MHz 54 54 54 54
1000 MHz 60 60 60 60
1100 MHz 72 72 72 72
1150 MHz 72 72 72 72

Note: Asterisks indicate the first frequency in the kernel which needs overvoltage.

===/sys/power/vdd1_opps_vsel values===

LV: "30 30 38 48 48 54 54 54 54 54 54 54 60 72 72"
ULV: "25 25 25 33 38 38 45 45 48 48 54 54 60 72 72"
XLV: "30 20 30 33 38 38 45 45 48 48 54 54 60 72 72"
ideal: "30 30 30 30 33 38 45 45 48 48 54 54 60 72 72"
starving:"22 22 28 29 32 34 41 42 45 46 49 52 55 63 69"

===Kernels' specifications===

====Nokia's kernel====

VALUE VOLTAGE FREQUENCY DYNAMIC POWER
30 0.975 V 0 MHz 0.000 V²/us
30 0.975 V 125 MHz 118.828 V²/us
38 1.075 V 250 MHz 288.906 V²/us
48 1.200 V 500 MHz 720.000 V²/us
54 1.275 V 550 MHz 894.094 V²/us
60 1.350 V 600 MHz 1093.500 V²/us

====titan's LV kernel====

VALUE VOLTAGE FREQUENCY DYNAMIC POWER
30 0.975V 0 MHz 0.000 V²/us
30 0.975V 125 MHz 118.828 V²/us
38 1.075V 250 MHz 288.906 V²/us
48 1.200V 500 MHz 720.000 V²/us
48 1.200V 550 MHz 792.000 V²/us
54 1.275V 600 MHz 975.375 V²/us
54 1.275V 700 MHz 1137.938 V²/us
54 1.275V 750 MHz 1219.219 V²/us
54 1.275V 810 MHz 1316.756 V²/us
54 1.275V 850 MHz 1381.781 V²/us
54 1.275V 900 MHz 1463.062 V²/us
54 1.275V 950 MHz 1544.344 V²/us
60 1.350V 1000 MHz 1822.500 V²/us
72 1.500V 1100 MHz 2475.000 V²/us
72 1.500V 1200 MHz 2700.000 V²/us

====titan's ULV kernel====

VALUE VOLTAGE FREQUENCY DYNAMIC POWER
25 0.912V 0 MHz 0.000 V²/us
25 0.912V 125 MHz 103.968 V²/us
25 0.912V 250 MHz 207.936 V²/us
33 1.012V 500 MHz 512.072 V²/us
38 1.075V 550 MHz 635.594 V²/us
38 1.075V 600 MHz 693.375 V²/us
45 1.163V 700 MHz 946.798 V²/us
45 1.163V 750 MHz 1014.427 V²/us
48 1.200V 810 MHz 1166.400 V²/us
48 1.200V 850 MHz 1224.000 V²/us
54 1.275V 900 MHz 1463.062 V²/us
54 1.275V 950 MHz 1544.344 V²/us
60 1.350V 1000 MHz 1822.500 V²/us
72 1.500V 1100 MHz 2475.000 V²/us
72 1.500V 1200 MHz 2700.000 V²/us

====titan's XLV kernel====

VALUE VOLTAGE FREQUENCY DYNAMIC POWER
30 0.975V 0 MHz 0.000 V²/us
20 0.850V 125 MHz 90.312 V²/us
30 0.975V 250 MHz 237.656 V²/us
33 1.012V 500 MHz 512.072 V²/us
38 1.075V 550 MHz 635.594 V²/us
38 1.075V 600 MHz 693.375 V²/us
45 1.163V 700 MHz 946.798 V²/us
45 1.163V 750 MHz 1014.427 V²/us
48 1.200V 810 MHz 1166.400 V²/us
48 1.200V 850 MHz 1224.000 V²/us
54 1.275V 900 MHz 1463.062 V²/us
54 1.275V 950 MHz 1544.344 V²/us
60 1.350V 1000 MHz 1822.500 V²/us
72 1.500V 1100 MHz 2475.000 V²/us
72 1.500V 1150 MHz 2587.500 V²/us

====titan's ideal kernel====

VALUE VOLTAGE FREQUENCY DYNAMIC POWER
30 0.975V 0 MHz 0.000 V²/us
30 0.975V 125 MHz 118.828 V²/us
30 0.975V 250 MHz 237.656 V²/us
30 0.975V 500 MHz 475.312 V²/us
33 1.012V 550 MHz 563.279 V²/us
38 1.075V 600 MHz 693.375 V²/us
45 1.163V 700 MHz 946.798 V²/us
45 1.163V 750 MHz 1014.427 V²/us
48 1.200V 810 MHz 1166.400 V²/us
48 1.200V 850 MHz 1224.000 V²/us
54 1.275V 900 MHz 1463.062 V²/us
54 1.275V 950 MHz 1544.344 V²/us
60 1.350V 1000 MHz 1822.500 V²/us
72 1.500V 1100 MHz 2475.000 V²/us
72 1.500V 1150 MHz 2587.500 V²/us

[[Category:Power users]]
[[Category:N900]]

Battery Saving

2011-05-17T14:04:49Z

94.174.1.22: /* Actions on phone lock/unlock */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. '''It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.'''

= Before you start =

== Set sensible defaults ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can.

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

== Use the Kernel for Power Users ==

Not just for [[Overclocking]], the [[Kernel_power]] package helps to save battery power and makes it easy to configure the kernel. You should be using this for power saving even if you never choose to go over the stock 600MHz.

== Enable SmartReflex ==

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and causes crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, but does not overclock above 805MHz.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock, basically to underclock the CPU (or at least, undo overclocking it) whilst the device is locked.

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Take IM / e-mail / other connections offline ==

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem. An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required.

The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

So, getting the phone to auto-downgrade to 2G is not hard (scripts to follow).

Slightly harder, though, is getting the phone to upgrade the connection again automatically when we do things that might require 3G. We certainly don't want to change the radio mode every time we unlock the phone, but we can do so on detecting the launch of known 3G applications (again assuming that we're not on a call at the time). However, these applications run within the user session, so you'll need to set up a second instance of DbusScripts running on the session bus in order to process the relevant events.

[[Category:Power users]]

Battery Saving

2011-05-17T13:32:03Z

94.174.1.22: /* Take connections offline */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. '''It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.'''

= Before you start =

== Set sensible defaults ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can.

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

== Use the Kernel for Power Users ==

Not just for [[Overclocking]], the [[Kernel_power]] package helps to save battery power and makes it easy to configure the kernel. You should be using this for power saving even if you never choose to go over the stock 600MHz.

== Enable SmartReflex ==

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and causes crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, but does not overclock above 805MHz.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock.

=== Change radio mode (non-invasively) ===

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Take IM / e-mail / other connections offline ==

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem. An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required.

The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

So, getting the phone to auto-downgrade to 2G is not hard (scripts to follow).

Slightly harder, though, is getting the phone to upgrade the connection again automatically when we do things that might require 3G. We certainly don't want to change the radio mode every time we unlock the phone, but we can do so on detecting the launch of known 3G applications (again assuming that we're not on a call at the time). However, these applications run within the user session, so you'll need to set up a second instance of DbusScripts running on the session bus in order to process the relevant events.

[[Category:Power users]]

Battery Saving

2011-05-17T13:29:56Z

94.174.1.22: /* Invasive power saving techniques */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. '''It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.'''

= Before you start =

== Set sensible defaults ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can.

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

== Use the Kernel for Power Users ==

Not just for [[Overclocking]], the [[Kernel_power]] package helps to save battery power and makes it easy to configure the kernel. You should be using this for power saving even if you never choose to go over the stock 600MHz.

== Enable SmartReflex ==

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and causes crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, but does not overclock above 805MHz.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock.

=== Change radio mode (non-invasively) ===

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Take connections offline ==

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem. An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required.

The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

So, getting the phone to auto-downgrade to 2G is not hard (scripts to follow).

Slightly harder, though, is getting the phone to upgrade the connection again automatically when we do things that might require 3G. We certainly don't want to change the radio mode every time we unlock the phone, but we can do so on detecting the launch of known 3G applications (again assuming that we're not on a call at the time). However, these applications run within the user session, so you'll need to set up a second instance of DbusScripts running on the session bus in order to process the relevant events.

[[Category:Power users]]

Battery Saving

2011-05-17T13:28:51Z

94.174.1.22: /* Do the obvious */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. '''It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.'''

= Before you start =

== Set sensible defaults ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can.

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

== Use the Kernel for Power Users ==

Not just for [[Overclocking]], the [[Kernel_power]] package helps to save battery power and makes it easy to configure the kernel. You should be using this for power saving even if you never choose to go over the stock 600MHz.

== Enable SmartReflex ==

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and causes crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, but does not overclock above 805MHz.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock.

=== Change radio mode (non-invasively) ===

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem. An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required.

The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

So, getting the phone to auto-downgrade to 2G is not hard (scripts to follow).

Slightly harder, though, is getting the phone to upgrade the connection again automatically when we do things that might require 3G. We certainly don't want to change the radio mode every time we unlock the phone, but we can do so on detecting the launch of known 3G applications (again assuming that we're not on a call at the time). However, these applications run within the user session, so you'll need to set up a second instance of DbusScripts running on the session bus in order to process the relevant events.

[[Category:Power users]]

Battery Saving

2011-05-17T13:25:23Z

94.174.1.22:

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. '''It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.'''

= Before you start =

== Do the obvious ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can.

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

== Use the Kernel for Power Users ==

Not just for [[Overclocking]], the [[Kernel_power]] package helps to save battery power and makes it easy to configure the kernel. You should be using this for power saving even if you never choose to go over the stock 600MHz.

== Enable SmartReflex ==

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and causes crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, but does not overclock above 805MHz.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock.

=== Change radio mode (non-invasively) ===

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem. An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required.

The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

So, getting the phone to auto-downgrade to 2G is not hard (scripts to follow).

Slightly harder, though, is getting the phone to upgrade the connection again automatically when we do things that might require 3G. We certainly don't want to change the radio mode every time we unlock the phone, but we can do so on detecting the launch of known 3G applications (again assuming that we're not on a call at the time). However, these applications run within the user session, so you'll need to set up a second instance of DbusScripts running on the session bus in order to process the relevant events.

[[Category:Power users]]

Battery Saving

2011-05-17T13:23:51Z

94.174.1.22:

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. '''It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.'''

= Before you start =

== Do the obvious ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can.

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Kernel settings ==

=== Use the Kernel for Power Users ===

Not just for [[Overclocking]], the [[Kernel_power]] package helps to save battery power and makes it easy to configure the kernel. You should be using this for power saving even if you never choose to go over the stock 600MHz.

=== Enable SmartReflex ===

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and causes crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, but does not overclock above 805MHz.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock.

=== Change radio mode (non-invasively) ===

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem. An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required.

The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

So, getting the phone to auto-downgrade to 2G is not hard (scripts to follow).

Slightly harder, though, is getting the phone to upgrade the connection again automatically when we do things that might require 3G. We certainly don't want to change the radio mode every time we unlock the phone, but we can do so on detecting the launch of known 3G applications (again assuming that we're not on a call at the time). However, these applications run within the user session, so you'll need to set up a second instance of DbusScripts running on the session bus in order to process the relevant events.

[[Category:Power users]]

Battery Saving

2011-05-17T01:02:58Z

94.174.1.22: /* Change radio mode */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.

= Before you start =

== Do the obvious ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can.

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Kernel settings ==

=== Use the Kernel for Power Users ===

Not just for [[Overclocking]], the [[Kernel_power]] package helps to save battery power and makes it easy to configure the kernel. You should be using this for power saving even if you never choose to go over the stock 600MHz.

=== Enable SmartReflex ===

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and causes crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, but does not overclock above 805MHz.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock.

=== Change radio mode (non-invasively) ===

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem. An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required.

The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

So, getting the phone to auto-downgrade to 2G is not hard (scripts to follow).

Slightly harder, though, is getting the phone to upgrade the connection again automatically when we do things that might require 3G. We certainly don't want to change the radio mode every time we unlock the phone, but we can do so on detecting the launch of known 3G applications (again assuming that we're not on a call at the time). However, these applications run within the user session, so you'll need to set up a second instance of DbusScripts running on the session bus in order to process the relevant events.

[[Category:Power users]]

Battery Saving

2011-05-17T00:24:21Z

94.174.1.22: /* Change radio mode */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.

= Before you start =

== Do the obvious ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can.

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Kernel settings ==

=== Use the Kernel for Power Users ===

Not just for [[Overclocking]], the [[Kernel_power]] package helps to save battery power and makes it easy to configure the kernel. You should be using this for power saving even if you never choose to go over the stock 600MHz.

=== Enable SmartReflex ===

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and causes crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, but does not overclock above 805MHz.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock.

=== Change radio mode (non-invasively) ===

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem. An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required. The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

[[Category:Power users]]

Battery Saving

2011-05-17T00:23:45Z

94.174.1.22: /* Change radio mode */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.

= Before you start =

== Do the obvious ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can.

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Kernel settings ==

=== Use the Kernel for Power Users ===

Not just for [[Overclocking]], the [[Kernel_power]] package helps to save battery power and makes it easy to configure the kernel. You should be using this for power saving even if you never choose to go over the stock 600MHz.

=== Enable SmartReflex ===

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and causes crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, but does not overclock above 805MHz.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock.

=== Change radio mode (non-invasively) ===

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Change radio mode ==

Keeping the phone in 2G mode except when 3G is needed for data will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine if you remember to use them before remaining battery life becomes a problem.

An alternative approach is to attempt to automate this such that the phone spends most of its working life (and makes and receives most calls) in 2G mode. We should then switch to dual mode when it is useful to do so, and switch back when it is no longer required.

The first part of this, the downgrade to 2G, is easy to script. We can do this any time the phone gets locked, provided we check that we're not on a call at the time. It's also nice to add a delay so that the phone only bothers to downgrade the radio mode if it gets locked and stays locked for a minute; we don't want it changing radio modes every time I throw the phone in my pocket to change buses. So, to achieve this:

* from our existing "on lock" script, we call a "try to set 2g" script
* have that script sleep for a while, to see if we unlock again
* have that script check for any good reasons it should not change radio mode
* have that script downgrade the radio mode to 2G

[[Category:Power users]]

Battery Saving

2011-05-16T22:47:44Z

94.174.1.22: /* Change radio mode */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.

= Before you start =

== Do the obvious ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can.

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Kernel settings ==

=== Use the Kernel for Power Users ===

Not just for [[Overclocking]], the [[Kernel_power]] package helps to save battery power and makes it easy to configure the kernel. You should be using this for power saving even if you never choose to go over the stock 600MHz.

=== Enable SmartReflex ===

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and causes crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, but does not overclock above 805MHz.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock.

=== Change radio mode (non-invasively) ===

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Change radio mode ==

Keeping the phone in 2G mode, except when 3G is needed for data, will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine, if you remember to use them before remaining battery life becomes a problem. The author is working on describing an approach to automating this using DbusScripts, risky but fun, to follow.

[[Category:Power users]]

Battery Saving

2011-05-16T22:37:35Z

94.174.1.22: /* Kernel settings */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.

= Before you start =

== Do the obvious ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can.

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Kernel settings ==

=== Use the Kernel for Power Users ===

Not just for [[Overclocking]], the [[Kernel_power]] package helps to save battery power and makes it easy to configure the kernel. You should be using this for power saving even if you never choose to go over the stock 600MHz.

=== Enable SmartReflex ===

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and causes crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, but does not overclock above 805MHz.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock.

=== Change radio mode (non-invasively) ===

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Change radio mode ==

Keeping the phone in 2G mode, except when 3G is needed for data, will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine, if you remember to use them before remaining battery life becomes a problem.

The author is working on describing an approach to automating this using DbusScripts, risky but fun, to follow.

[[Category:Power users]]

Battery Saving

2011-05-16T22:36:29Z

94.174.1.22: /* Invasive power saving */

This page aims to document "power user" techniques for extending battery life, i.e. automating various aspects of the phone's behaviour with a view to extending battery life. It is currently a stub/work in progress; the aim is not to reinvent the wheel but to draw together a variety of approaches to battery saving.

= Before you start =

== Do the obvious ==

The techniques here all involve automating the process of turning various things on or off according to the activity of the phone. Before there's any point in doing this, you'll want to have set the phone up more or less the way you like it, turned off anything you don't use, set reasonable defaults and made such optimisations as you can.

== Install the relevant applications ==

You'll need [[DbusScripts]] and [[Kernel_power]] and you'll also want to have installed the status menu applets for manually adjusting screen brightness, radio switching, etc.

= Background power saving techniques =

Techniques in the "background power saving" section should have little or no negative impact on the performance or usability of the phone but should save power in the background when the phone is not actively being used.

== Kernel settings ==

=== Use the Kernel for Power Users ===

Not just for [[Overclocking]], the [[Kernel_power]] package helps to save battery power and makes it easy to configure the kernel. You should be using this for power saving, even if you never choose to go over the stock 600MHz.

=== Enable SmartReflex ===

Reports are mixed on SmartReflex; some users report crashes, while others use it with no problems and report improved battery life. There seems to be general concensus that it limits overclocking to 805 MHz and causes crashes in combination with overclocking above that figure. The author uses SmartReflex on VDD1 and VDD2 without problems, but does not overclock above 805MHz.

== Actions on phone lock/unlock ==

One of the simplest uses of [[DbusScripts]] is to detect when the phone is locked or unlocked and run scripts to reduce the cpu frequency, system load, etc.

=== Suspend user processes ===
See Xagoln's post: http://talk.maemo.org/showpost.php?p=1005668&postcount=1

=== Change kernel powersave bias ===
Over on the [[Overclocking]] page, Fecn describes a set of scripts to modify the [[Kernel_power]] settings on phone lock/unlock.

=== Change radio mode (non-invasively) ===

= Invasive power saving techniques =

Techniques in the "invasive power saving" section save power by intentionally limiting the activity and/or functionality of the phone. This can have unintended consequences, so be sure you understand what you are instructing the phone to do before you do it.

== Change radio mode ==

Keeping the phone in 2G mode, except when 3G is needed for data, will seriously enhance battery life at the possible expense of

* not having 3G connected per default when you launch a 3G application
* interrupting any Internet connections/phone calls when radio mode is changed
* forcing any background Internet traffic to GPRS
* impacting on viability of some messenger services, notably MSN

Therefore, many users drop to 2G mode manually, using something like qwerty12's [http://talk.maemo.org/showthread.php?t=39725 3G/2G Mode Selection Applet] or [http://blog.dawid.lorenz.co/2010/05/saving-n900-battery-power-with-simple_445.html David Lorenz's power saving script.] These work fine, if you remember to use them before remaining battery life becomes a problem.

The author is working on describing an approach to automating this using DbusScripts, risky but fun, to follow.

[[Category:Power users]]

Battery Saving

2011-05-16T22:14:24Z

94.174.1.22: /* Change kernel powersave bias */

Battery Saving

2011-05-16T09:50:59Z

94.174.1.22: /* Before you start */

Battery Saving

2011-05-16T09:47:24Z

94.174.1.22:

Battery Saving

2011-05-15T23:43:10Z

94.174.1.22: /* Actions on phone lock/unlock */

Battery Saving

2011-05-15T23:41:23Z

94.174.1.22: /* Actions on phone lock/unlock */