Toshiyuki Imamura
The University of Electro-Communications

"Automatic Tuning for Collective Communication Operations"

Collective communication, especially broadcast or allreduce, plays a great role in parallel programming. Optimal algorithms of collective communication depend on the topology of the candidate processes and network, and the message counts. Since these factors are dynamically varied, it is better to choose the communication algorithm in every execution. This study covers an idea of auto-tuned collective communication as a new application of the auto-tuning methodology.