Parallel computing is entering the era of petascale machines. This era brings enormous computing power to us and new challenges to harness this power efficiently. Machines with hundreds of thousands of processors already exist, connected by complex interconnect topologies. Network contention is becoming an increasingly important factor affecting overall performance. The farther different messages travel on the network, greater is the chance of resource sharing between messages and hence, of contention. Recent studies on IBM Blue Gene and Cray XT machines have shown that under contention, message latencies can be severely affected.

Mapping of communicating tasks on nearby processors can minimize contention and lead to better application performance. In this talk, I will propose algorithms and techniques for automatic mapping of parallel applications to relieve the application developers of this burden. I will first demonstrate the effect of contention on message latencies and use these studies to guide the design of mapping algorithms. I will introduce the hop-bytes metric for the evaluation of mapping algorithms and suggest that it is a better metric than the previously used maximum dilation metric. I will then discuss in some detail, the mapping framework which comprises of topology aware mapping algorithms for parallel applications with regular and irregular communication patterns.

I will also briefly discuss my interests within and future ideas for parallel computing research. More details on my research available at: http://charm.cs.illinois.edu/~bhatele/phd/
 

Biography

Abhinav received a B. Tech. degree in Computer Science and Engineering from I.I.T. Kanpur (INDIA) in May 2005 and a M. S. degree in Computer Science from the University of Illinois at Urbana-Champaign in 2007. He is a 5th year Ph.D. student at the Parallel Programming Lab at the University of Illinois, working with Prof. Laxmikant V. Kale. His research is centered around topology aware mapping and load balancing for parallel applications. Abhinav has received the David J. Kuck Outstanding MS Thesis Award in 2009, Third Prize in the ACM Student Research Competition at SC 2008, a Distinguished Paper Award at Euro-Par 2009 and the George Michael HPC Fellowship Award at SC 2009.