Energy Footprint of Advanced Dense Numerical Linear Algebra Using Tile Algorithms on Multicore Architectures

• Published in: 2012 International Conference on Cloud and Green Computing pp. 274 - 281
• Main Authors: Dongarra, J., Ltaief, Hatem, Luszczek, P., Weaver, V. M.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01.11.2012
• Subjects: Dense Linear Algebra; Dynamic Scheduling; Heuristic algorithms; Libraries; Linear algebra; Mixed Precision Algorithms; Parallel processing; Plasmas; Power Consumption; Power measurement; PowerPack; RAPL; Tile Algorithms; Tiles; Tree Reduction
• ISBN: 1467330272; 9781467330275
• DOI: 10.1109/CGC.2012.113

We propose to study the impact on the energy footprint of two advanced algorithmic strategies in the context of high performance dense linear algebra libraries: (1) mixed precision algorithms with iterative refinement allow to run at the peak performance of single precision floating-point arithmetic while achieving double precision accuracy and (2) tree reduction technique exposes more parallelism when factorizing tall and skinny matrices for solving over determined systems of linear equations or calculating the singular value decomposition. Integrated within the PLASMA library using tile algorithms, which will eventually supersede the block algorithms from LAPACK, both strategies further excel in performance in the presence of a dynamic task scheduler while targeting multicore architecture. Energy consumption measurements are reported along with parallel performance numbers on a dual-socket quad-core Intel Xeon as well as a quad-socket quad-core Intel Sandy Bridge chip, both providing component-based energy monitoring at all levels of the system, through the Power Pack framework and the Running Average Power Limit model, respectively.