A Case for Machine Learning to Optimize Multicore Performance


Authors: Archana Ganapathi, Kaushik Datta, Armando Fox, David Patterson
Venue: USENIX Hot Topics in Parallelism 2009

This workshop paper examines applying a machine learning technique to auto-tuning HPC stencils. The configuration space consists of 5 independent knobs resulting in a total of ~4 million possible configurations. The work applies KCCA (kernel canonical correlation analysis) which finds correlations between two sets of data, in this case performance measurements and tune settings. KCCA is a specific way to do this that allows for non-linear relationships. Compared to feature extraction techniques, this is a direct way to find correlations rather than just using an intermediate step of feature extraction followed by a method of clustering. The main reason this appears to be only a workshop paper is that only two experiments are performed, both using stencils. The KCCA algorithm is definitely worth a deeper understanding, as the results are promising.

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