Proceedings 2001 International Conference on Parallel Architectures and Compilation Techniques (2001)
Sept. 8, 2001 to Sept. 12, 2001
María Jesús Garzarán , Universidad de Zaragoza
Milos Prvulovic , University of Illinois at Urbana-Champaign
Ye Zhangy , University of Illinois at Urbana-Champaign
Josep Torrellas , University of Illinois at Urbana-Champaign
Alin Jula , Texas A&M University
Hao Yu , Texas A&M University
Lawrence Rauchwerger , Texas A&M University
Abstract: Reductions are important and time-consuming operations in many scientific codes. Effective parallelization of reductions is a critical transformation for loop parallelization, especially for sparse, dynamic applications. Unfortunately, conventional reduction parallelization algorithms are not scalable. In this paper, we present new architectural support that significantly speeds-up parallel reduction and makes it scalable in shared-memory multiprocessors. The required architectural changes are mostly confined to the directory controllers. Experimental results based on simulations show that the proposed support is very effective. While conventional software-only reduction parallelization delivers average speedups of only 2.7 for 16 processors, our scheme delivers average speedups of 7.6.
L. Rauchwerger et al., "Architectural Support for Parallel Reductions in Scalable Shared-Memory Multiprocessors," Proceedings 2001 International Conference on Parallel Architectures and Compilation Techniques(PACT), Barcelona, Spain, 2001, pp. 0243.