The Workshop on the Interface of Statistics and Optimization (WISO) at Duke University’s Penn Pavilion wrapped up recently. After we said good bye to all of our participants, I was reminded of an interesting talk given by one of the twelve insightful speakers. The speaker in question was Jack Dongarra.
Jack is the Director of the Center for Information Technology Research and Innovative Computing Laboratory, from the University of Tennessee. He lectured on: “The Road to Exascale and Legacy Software for Dense Linear Algebra (or what we have been doing for the last 43 years).” Jack’s talk at WISO could be appreciated even by those who are not specialists in the esoteric matters of statistics and optimization. True to the title, Jack has been designing high-performance software for over 40 years. His pioneering work has been honored with many awards, including membership in the US National Academy of Engineering.
Twice a year, Jack co-publishes a benchmark of the 500 most powerful supercomputers in the world. The current number one, as of November 2016, is the Sunway TaihuLight machine in Wuxi, China. Built from over 10 million processors, it can execute more than 1016 operations in a single second. The Titan Cray XK7 at Oak Ridge National Lab, located in Oak Ridge, TN, is number three.
For the many young people in the audience, Jack started his talk with a history of how hardware and software have developed over the years, and how he himself got into the business of benchmarking. A few photos from the 1970’s, featuring Jack and his colleagues in bell bottoms and side burns, proudly posing on a Ford Pinto with the license plate “Linpack” (after their groundbreaking public-domain software package) were well received.
Jack’s advice for how to build good software: Keep the processors busy with arithmetic, make sure they coordinate their work schedules efficiently rather than sitting idle waiting for results from other processors.
Jack ended with a list of the many challenges for software design, including:
- Efficiency (speed matters),
- Scalability (keep up the efficiency, even in the face of growing work),
- Reliability (with 10 million processors in use, some are bound to fail)
- Portability (the particular hardware platform should not matter).
Jack Dongarra was one of many interesting speakers at the WISO. If you are interested in seeing the other presentations from the 3-day event, visit the WISO Video Page.