TY - GEN
T1 - Using Additive Modifications in LU Factorization Instead of Pivoting
AU - Lindquist, Neil
AU - Luszczek, Piotr
AU - Dongarra, Jack
N1 - Publisher Copyright:
© 2023 ACM.
PY - 2023/6/21
Y1 - 2023/6/21
N2 - Direct solvers for dense systems of linear equations commonly use partial pivoting to ensure numerical stability. However, pivoting can introduce significant performance overheads, such as synchronization and data movement, particularly on distributed systems. To improve the performance of these solvers, we present an alternative to pivoting in which numerical stability is obtained through additive updates. We implemented this approach using SLATE, a GPU-accelerated numerical linear algebra library, and evaluated it on the Summit supercomputer. Our approach provides better performance (up to 5-fold speedup) than Gaussian elimination with partial pivoting for comparable accuracy on most of the tested matrices. It also provides better accuracy (up to 15 more digits) than Gaussian elimination with no pivoting for comparable performance.
AB - Direct solvers for dense systems of linear equations commonly use partial pivoting to ensure numerical stability. However, pivoting can introduce significant performance overheads, such as synchronization and data movement, particularly on distributed systems. To improve the performance of these solvers, we present an alternative to pivoting in which numerical stability is obtained through additive updates. We implemented this approach using SLATE, a GPU-accelerated numerical linear algebra library, and evaluated it on the Summit supercomputer. Our approach provides better performance (up to 5-fold speedup) than Gaussian elimination with partial pivoting for comparable accuracy on most of the tested matrices. It also provides better accuracy (up to 15 more digits) than Gaussian elimination with no pivoting for comparable performance.
KW - LU factorization
KW - communication avoidance
KW - linear algebra
UR - http://www.scopus.com/inward/record.url?scp=85168416544&partnerID=8YFLogxK
U2 - 10.1145/3577193.3593731
DO - 10.1145/3577193.3593731
M3 - Conference contribution
AN - SCOPUS:85168416544
T3 - Proceedings of the International Conference on Supercomputing
SP - 14
EP - 24
BT - ACM ICS 2023 - Proceedings of the International Conference on Supercomputing
PB - Association for Computing Machinery
T2 - 37th ACM International Conference on Supercomputing, ICS 2023
Y2 - 21 June 2023 through 23 June 2023
ER -