Dig out dead looping thread

It is not easy to write multi-threading applications. One of the common bugs is dead looping of a thread. To kill this kind of bugs, the first step is to find out which thread causes dead looping. However, an application may have dozens of threads. How to dig out the dead looping thread? My trick is to issue the ps -eLf command to list the information of threads in the whole system. The "time" column of the output of ps shows the CPU time have spent by the threads. Most likely, the dead looping thread would be the thread spending most CPU time. Then, drop down the LWP number of the thread. Next, you use gdb to attach the process and to debug the thread.