Y-Tune: Performance Portability Using Compiler-Directed Autotuning

Mary Hall
Seminar

As current and future architectures becomes increasingly diverse, the challenges of developing high-performance applications are becoming more onerous. The goal of compiler optimization in high-performance computing is to take as input a computation that is architecture independent and maintainable and produce as output efficient implementations of the computation that are specialized for the target architecture. A compiler that is specialized for an application domain can tailor its optimization strategy to increase effectiveness. Autotuning empirically evaluates a search space of possible implementations of a computation to identify the implementation that best meets its optimization criteria (e.g., performance, power, or both). Combining the three concepts, autotuning compilers generate this search space of highly-tuned implementations either automatically or with programmer guidance. This talk will explore the role of compiler-based specialization and autotuning in achieving very high levels of performance, comparable to what is obtained manually by experts. We will consider three case studies using this approach to highlight some of the aggressive optimizations required to achieve this goal: geometric multigrid and the stencil computations within them, tensor contractions and sparse matrix computations.
   
Bio: Mary Hall is a professor in the School of Computing at University of Utah. She received a PhD in Computer Science in 1991 from Rice University. Her research focuses on compiler technology for exploiting performance-enhancing features of a variety of computer architectures: automatic parallelization for multi-cores and GPUs, superword-level parallelism, processing-in-memory architectures and FPGAs. Professor Hall is an ACM Distinguished Scientist and ACM’s representative on the Computing Research Association Board of Directors. She is deeply interested in computing history, having served on the ACM History Committee since 2005 and as chair from 2009-2014. She also actively participates in outreach programs to encourage the participation of women and other underrepresented groups in computer science.