Author : University of Wisconsin--Madison. Computer Sciences Dept
Publisher :
ISBN 13 :
Total Pages : 13 pages
Book Rating : 4.:/5 (353 download)
Book Synopsis An Analysis of the Interactions of Overhead-reducing Techniques for Shared-memory Multiprocessors by : University of Wisconsin--Madison. Computer Sciences Dept
Download or read book An Analysis of the Interactions of Overhead-reducing Techniques for Shared-memory Multiprocessors written by University of Wisconsin--Madison. Computer Sciences Dept and published by . This book was released on 1995 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: "The fine-grain nature of shared-memory multiprocessor communication introduces overheads that can be substantial. Using the Scalable Coherent Interface (SCI) as a base hardware platform and the SPLASH benchmark suite for applications, we analyze three techniques to reduce this overhead: (i) efficient synchronization primitives, and in particular a hardware primitive called QOLB; (ii) weakened memory ordering constraints; and (iii) optimization of the cache-coherence protocol for two nodes sharing data. We perform simulations both for current technology and technology that we anticipate will be available five years hence. We find that QOLB (of which this study performs the first detailed simulations) shows a large and consistent improvement, much larger than that predicted by Mellor-Crummey and Scott [19]. The relaxation of memory ordering constraints also provides a consistent performance improvement. In accordance with prior results, we show that a more aggressive memory model produces more substantial performance improvements. The optimization for two-node sharing shows mixed results, correlating unsurprisingly with the presence of that sharing pattern in an application. Our most important results are (i) that the overheads eliminated with these optimizations are largely orthogonal -- the performance gains from supporting multiple optimizations concurrently are for the most part additive -- and (ii) that technological improvements increase both these overheads and the success of the optimizations at reducing them."
