Debugging and Tuning Map-Reduce Applications
by Arun C Murthy, Principal Engineer at Yahoo! and Member of Apache Hadoop PMC
Arun covers simple home-made remedies for peering into the Hadoop Map-Reduce framework as it crunches your data. This wide-ranging discussion covers topics such as using debuggers/profilers on your applications, using Map-Reduce Counters, other simple ways to tune your applications, and how to avoid common pitfalls.
Link to this presentation: http://www.scribd.com/doc/7588384/Debugging-and-Tuning-MapReduce-Applications