Potential power sapping issue/cause

[Guest Brins0]

Looking in LogCat, there's a potential power sapping report being broadcast multiple times per second whilst the screen is touched:

E/ViewRoot enter ( 4787): Dispatching touchevent to com.android.internal.policy.impl.PhoneWindow$DecorView@32e971b0 touchevent action is 2 X= 240.91109 Y=396.66116

E/ViewRoot exit ( 4787): Dispatching touchevent to com.android.internal.policy.impl.PhoneWindow$DecorView@32e971b0

W/WindowManager(  124): waitForLastKey: mFinished=true, mLastWin=null

This causes the CPU clock to raise to ~100% whilst the screen is being touched. I haven't noticed this on my other phones, and they do not spike when the screen is touched. It may be worth investigating these reports to see if it can save any power when the device is in use.

On the topic of CPU clock, I'm sure it would be possible to reduce the minimum clock frequency of the device to 128MHz as opposed to 256MHz, to further reduce idle power consumption. This frequency is supported by the processor, it just needs kernel mods (I presume) to enable that frequency for use.

Edited November 6, 2010 by Brins0

[Guest chall32]

Just to complete the circle (for future searches etc), we are discussing the touchscreen high CPU issue here: http://android.modaco.com/content-page/325...reeze/page/100/ Post 105 onwards...

Re minimum CPU frequency, yes this would be enabled in the Kernel. One of the Kernel Dev's (kallt_kaffe / TomG / etc) would be able to comment further. :unsure: From memory, I think that this looked into for the T-Mob Pulse / Huawei U8220.

- Chris