Programming Parallel Dense Matrix Factorizations with Look-Ahead and OpenMP

Autor:	Catalán, Sandra, Castelló, Adrián, Igual, Francisco D., Rodríguez-Sánchez, Rafael, Quintana-Ortí, Enrique S.
Rok vydání:	2018
Předmět:	Computer Science - Distributed Parallel and Cluster Computing Computer Science - Mathematical Software
Druh dokumentu:	Working Paper
Popis:	We investigate a parallelization strategy for dense matrix factorization (DMF) algorithms, using OpenMP, that departs from the legacy (or conventional) solution, which simply extracts concurrency from a multithreaded version of BLAS. This approach is also different from the more sophisticated runtime-assisted implementations, which decompose the operation into tasks and identify dependencies via directives and runtime support. Instead, our strategy attains high performance by explicitly embedding a static look-ahead technique into the DMF code, in order to overcome the performance bottleneck of the panel factorization, and realizing the trailing update via a cache-aware multi-threaded implementation of the BLAS. Although the parallel algorithms are specified with a highlevel of abstraction, the actual implementation can be easily derived from them, paving the road to deriving a high performance implementation of a considerable fraction of LAPACK functionality on any multicore platform with an OpenMP-like runtime. Comment: 28 pages
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/1804.07017 Zobrazit plný text záznamu View this record from Arxiv