Hello, I have a question about mapred.Child processes. Even though a mapper is finished I see that the process (from ps) stays around longer than reported on the hadoop MR webpage. What is the mapper process doing after it has reported that it is finished? To illustrate my question: I see that one mapper reports it finished in 9 seconds but from logging ps output every second, I see it last for 24 seconds before exiting. I essentially see this for each mapper.
Lastly, where can I find information on how exactly the map reduce framework reuses JVMs. The reason I'm asking is because I see that with reuse on (mapred.job.reuse.jvm.num.tasks set to -1), the pid's change for each new mapper. How can this be without starting a new JVM? Thanks! -- Navraj S. Chohan nlak...@gmail.com
