Guy Blelloch Professor Website ORCiD Office 9211 Gates and Hillman Centers Email gb1y@andrew.cmu.edu Phone (412) 268-6245 Department Computer Science Department Administrative Support Person Matt McMonagle Research Interests Algorithms and Complexity Programming Languages CSD Courses Taught 15852 - Spring, 2024 Research/Teaching Statement My main research interest is in the interaction between algorithms and languages, mostly in the context of parallel computing, and has consisted of both theoretical and experimental work. As programming languages become higher level, implementations become more complex, and parallelism becomes pervasive, users are naturally becoming more removed from the hardware and its costs. Rather than trying to bring programmers down to the level of the machine to understand and get good performance, however, I believe that we should be trying to bring languages and cost models up to the level of the programmer. My research therefore centers around questions of how to model costs (e.g. time and space) for very-high level programming constructs (e.g. dynamic parallelism, futures, garbage collection), of how to design systems so these costs have meaning, and of how to make use of these features in effective algorithms design. My recent work includes work on the PSCICO project with Gary Miller, Bob Harper and Peter Lee. Here we are looking at how to use very-high level programming constructs in geometric and scientific algorithms. We hope this project will give guidance to future language design, and will identify new ways of thinking about algorithm implementation. I also work on applied algorithms, parallel garbage collection, parallel scheduling, efficient parallel algorithms, and continue to work, to some extent, on the NESL programming language, a parallel language that my students and I developed in the early 90s. Publications Conference ParlayANN: Scalable and Deterministic Parallel Graph-Based Approximate Nearest Neighbor Search Algorithms 2024 • Proceedings of the ACM SIGPLAN Symposium on Principles and Practice of Parallel Programming, PPOPP • 270-285 Manohar MD, Shen Z, Blelloch GE, Dhulipala L, Gu Y, Simhadri HV, Sun Y Conference verlib: Concurrent Versioned Pointers 2024 • Proceedings of the ACM SIGPLAN Symposium on Principles and Practice of Parallel Programming, PPOPP • 200-214 Blelloch GE, Wei Y Journal Article Parallel Minimum Cuts in O(m log<SUP>2</SUP> n) Work and Low Depth 2023 • ACM Transactions on Parallel Computing • 10(4): Anderson D, Blelloch GE Conference PIM-tree: A Skew-resistant Index for Processing-in-Memory (Abstract) 2023 • HOPC 2023 - Proceedings of the 2023 ACM Workshop on Highlights of Parallel Computing • 13-14 Kang H, Zhao Y, Blelloch GE, Dhulipala L, Gu Y, Mcguffey C, Gibbons PB Conference PIM-trie: A Skew-resistant Trie for Processing-in-Memory 2023 • PROCEEDINGS OF THE 35TH ACM SYMPOSIUM ON PARALLELISM IN ALGORITHMS AND ARCHITECTURES, SPAA 2023 • 1-14 Kang H, Zhao Y, Blelloch GE, Dhulipala L, Gu Y, McGuffey C, Gibbons PB
Conference ParlayANN: Scalable and Deterministic Parallel Graph-Based Approximate Nearest Neighbor Search Algorithms 2024 • Proceedings of the ACM SIGPLAN Symposium on Principles and Practice of Parallel Programming, PPOPP • 270-285 Manohar MD, Shen Z, Blelloch GE, Dhulipala L, Gu Y, Simhadri HV, Sun Y
Conference verlib: Concurrent Versioned Pointers 2024 • Proceedings of the ACM SIGPLAN Symposium on Principles and Practice of Parallel Programming, PPOPP • 200-214 Blelloch GE, Wei Y
Journal Article Parallel Minimum Cuts in O(m log<SUP>2</SUP> n) Work and Low Depth 2023 • ACM Transactions on Parallel Computing • 10(4): Anderson D, Blelloch GE
Conference PIM-tree: A Skew-resistant Index for Processing-in-Memory (Abstract) 2023 • HOPC 2023 - Proceedings of the 2023 ACM Workshop on Highlights of Parallel Computing • 13-14 Kang H, Zhao Y, Blelloch GE, Dhulipala L, Gu Y, Mcguffey C, Gibbons PB
Conference PIM-trie: A Skew-resistant Trie for Processing-in-Memory 2023 • PROCEEDINGS OF THE 35TH ACM SYMPOSIUM ON PARALLELISM IN ALGORITHMS AND ARCHITECTURES, SPAA 2023 • 1-14 Kang H, Zhao Y, Blelloch GE, Dhulipala L, Gu Y, McGuffey C, Gibbons PB