android cgroup doesn't work for thread priority?

view full story

http://stackoverflow.com – from https://plus.google.com/u/0/105051985738280261832/posts/XAZ4CeVP6DC , it is said that the thread that is set with BACKGROUND priority will be put into specific cgroups which will consume at most 10% CPU. I want to limit the CPU usage of a task in my application, so I set the priority as BACKGROUND, but it seems not work. So I wrote a simple application to test it and found it will consume the same CPU as the one with DEFAULT priority. I checked the cgroup of both thread, one is in apps cgroup, and the other one is in apps/bg_non_interactive cgroup. public class TestThreadPriority { (HowTos)