Quick Profiling HOWTO:

Install gprof2dot.py into your $PATH:
http://code.google.com/p/jrfonseca/wiki/Gprof2Dot
Also install graphviz (to render PNGs) and feh (image viewer).

Now run

./test_performance.py -c 1 -s load_ora

For more options see

./test_performance.py -h


You can also start the profiler from within MyPaint (Menu->Help->Debug).
Works best with a keyboard shortcut assigned through the menu.

Use the results with care. There is profiler overhead, the work being
done while idling will sum up (eg. just hovering with the stylus), and
xorg is probably filtered out completely.

To profile the code written in C you have to use something else
(eg. oprofile).