To improve performance of large-scale scientific applications, scientists or tuning experts make various empirical attempts to change compiler options, program parameters or even the syntactic structure of programs. Those attempts followed by performance evaluation are repeated until satisfactory results are obtained. On account of combinatorial explosion of possible attempts, the task of performance tuning requires a great deal of time and effort, and hence scientists/tuning experts have a tendency to make decisions on what to be explored just based on their intuition or good sense of tuning. We advocate evidence-based performance tuning (EBT) that facilitates the use of database of facts extracted from tuning histories of applications to navigate the search space. However, in general, performance tuning is conducted as transient tasks without revision control systems. Tuning histories may lack explicit facts about what kind of program transformation contributed to the better performance or even about the chronological order of the source code snapshots. For reconstructing the missing information, we employ a state-of-the-art fine-grained change pattern identification tool for inferring applied transformation patterns only from an unordered set of source code snapshots. This paper reports on experiments of tuning pattern identification followed by predictive model construction conducted for a few scientific applications tuned for the K supercomputer.
Reference
Masatomo Hashimoto, Masaaki Terai, Toshiyuki Maeda, and Kazuo Minami. Extracting Facts from Performance Tuning History of Scientific Applications for Predicting Effective Optimization Patterns. In Proceedings of the 12th Working Conference on Mining Software Repositories (MSR2015), pp. 13-23, 2015.