TOP    Events & Outreach    R-CCS Cafe    The 275th R-CCS Cafe (Dec 13, 2024)

Details
Date Fri, Dec 13, 2024
Time 3:00 pm - 4:00 pm (3:00 pm - 3:20 pm Talks, 3:20 pm - 3:30 Discussions, 3:30 pm - 4:00 pm Free discussion and coffee break)
City Kobe, Japan/Online
Place

Lecture Hall (6th floor) at R-CCS, Online seminar on Zoom

  • If you are not affiliated with R-CCS and would like to attend R-CCS Cafe, please email us at r-ccs-cafe[at]ml.riken.jp.
Language Presentation Language: English
Presentation Material: English
Speakers

Yuki Uchino

Large-Scale Parallel Numerical Computing Technology Research Team
Postdoctoral Researcher

Talk Titles and Abstracts

Speaker: Yuki Uchino

Title:
High-Performance Eigensolver Combining EigenExa and Iterative Refinement
Abstract:
This study proposes a high-performance and reliable eigensolver via mixed-precision arithmetic between ordinary and highly-accurate precisions. Eigenvalue decomposition is ubiquitous in simulations. Various eigensolvers for computing approximations have been developed thus far. If eigenvalues are narrowly clustered, the computation of eigenvectors may be ill-posed. Thus, the computed eigenpairs may not be sufficiently accurate and lack reliability. In this study, we introduce mixed-precision iterative refinement methods to improve the accuracy of eigenvectors obtained using numerical methods. This approach contributes to obtaining sufficiently accurate results without arbitrary precision eigensolvers. We construct a high-performance and reliable eigensolver by combining the iterative refinement methods and EigenExa, a modern high-performance solver for large-scale and highly parallel computations. Numerical experiment results demonstrate the accuracy of the results and performance benchmark of the proposed approach.

Important Notes

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(Dec 9, 2024)