Lawrence Berkeley National Laboratory
A 3D Parallel Algorithm for QR Decomposition
- Author(s): Ballard, Grey
- Demmel, James
- Grigori, Laura
- Jacquelin, Mathias
- Knight, Nicholas
- et al.
Published Web Locationhttps://doi.org/10.1145/3210377.3210415
© 2018 Association for Computing Machinery. Interprocessor communication often dominates the runtime of large matrix computations. We present a parallel algorithm for computing QR decompositions whose bandwidth cost (communication volume) can be decreased at the cost of increasing its latency cost (number of messages). By varying a parameter to navigate the bandwidth/latency tradeoff, we can tune this algorithm for machines with different communication costs.