Cache-efficient Dynamic Programming Algorithms for Multicores

Rezaul Alam Chowdhury and Vijaya Ramachandran

Technical Report TR-08-16
The University of Texas at Austin, Department of Computer Sciences, Apr. 2008, 21 pages


We present cache-efficient chip multiprocessor (CMP) algorithms with good speed-up for some widely used dynamic programming algorithms. We consider three types of caching systems for CMPs: D-CMP with a private cache for each core, S-CMP with a single cache shared by all cores, and Multicore, which has private L1 caches and a shared L2 cache. We derive results for three classes of problems: local dependency dynamic programming (LDDP), Gaussian Elimination Paradigm (GEP), and parenthesis problem.

For each class of problems, we develop a generic CMP algorithm with an associated tiling sequence. We then tailor this tiling sequence to each caching model and provide a parallel schedule that results in a cache-efficient parallel execution up to the critical path length of the underlying dynamic programming algorithm.

We present experimental results on an 8-core Opteron for two sequence alignment problems that are important examples of LDDP. Our experimental results show good speed-ups for simple versions of our algorithms.

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