[maemo-developers] [maemo-developers] Re: [maemo-users] Battery Benchmarking?

[From: Eero Tamminen]

Hi,

ext Igor Stoppa wrote:
 > As Amit wrote, when you move to 3rd party applications it's very
 > likely that one of those is buggy and does not behave properly
 > (i.e. drains the battery while doing nothing).

Process should not be doing anything (except sit in select() without
timeouts) when it's not visible.  Exceptions to this could be something
like playing music or downloading files on the background, but this
is always something that user specifically initiates / requests for,
not something done by default.


 > Unfortunately that sort of bug is harder to spot.

First use "top" to check that no process is busy.  After that use
"strace -p <PID>" to check non-visible application processes (or
services) to see that they are not doing any polling (calling
systemcalls continuously).

Strace does not catch apps that do not call any syscalls but keep the
CPU  otherwise busy.  However, one sees those kind of proceses in
"top".


One good example of something that is busy while doing nothing is
libSDL.  Do not leave 3rd party SDL games/apps running when you're not
using them!


     - Eero