[TESTING] SCBS: Improved battery meter system

[toadlife]

Originally Posted by steveholtam

I think I am getting reduced battery life because of the SCBS addition to the kernel. Prior to this, I would get to 5pm or 6pm before getting into the red. Since the new addition, I'm getting to about two hours less battery life.

If I can find the prior kernel, I'm just going to switch back.

You may want to try just switching to the non-scbs rootfs, as it might be the scbs program (which is in the rootfs) draining your battery and not the kernel changes. I've stopped using scbs myself due to the fact that it seemed to be causing instability in my phone.

[jonpry]

It definitely uses power, about 2ma by my measurements. I get about 70 hours on my 210.

[ndno]

Originally Posted by jonpry

It definitely uses power, about 2ma by my measurements. I get about 70 hours on my 210.

Is there any way to reduce its activity? When it runs in daemon mode, does it exchange data with the scbs-supported kernel, "telling" it how to manage the battery meter as well as charging?

[jonpry]

Not really. The kernel takes battery measurements every 5 seconds, while sleeping or not, and then pipes this data to the daemon which processes the numbers and computes a percentage. The percentage is then sent back to the kernel so it can be presented on the old interface that all htc libhardware's want to use. The measurements have to be fairly often to reduce noise. I really don't see the problem though at 70 hours it is a 10% reduction in life. With more usage, say your only getting 24 hours, its like 3%. At 8 hours its only 1.

[manekineko]

Originally Posted by jonpry

Not really. The kernel takes battery measurements every 5 seconds, while sleeping or not, and then pipes this data to the daemon which processes the numbers and computes a percentage. The percentage is then sent back to the kernel so it can be presented on the old interface that all htc libhardware's want to use. The measurements have to be fairly often to reduce noise. I really don't see the problem though at 70 hours it is a 10% reduction in life. With more usage, say your only getting 24 hours, its like 3%. At 8 hours its only 1.

How does the previous battery algorithm XDAndroid has been using avoid draining the battery with its calculations? Presumably, it too had to run fairly frequent calculations in order to have something to display.

[highlandsun]

The previous algorithm woke up every 10 seconds and re-computed everything.

[manekineko]

Originally Posted by highlandsun

The previous algorithm woke up every 10 seconds and re-computed everything.

So is the increased battery drain from SCBS just moving from 10 second polling to 5 second or is there more to it?