I am trying to profile mapreduce task using operf.
I have some troubles with getting correct symbols of java threads.

What I did was to operf the tasktracker which spawns map and reduce tasks (threads).
I did like the following to start the tasktracker.
operf /usr/lib/jvm/java-oracle/bin/java -agentlib:jvmti_oprofile ......

However, only the tasktracker thread gets the correct symbols for all addresses. I found that only one ".jo" file is created for the tasktracker, not the child threads that inherit the tasktracker, such as map and reduce tasks. All the child threads get "anon".

Please help me to resolve the issue.
Thank you very much.