Scientific Computing Seminar

Date:

Friday 11 June 2004

Time:

1:00pm-2:00pm

Location:

50A-5132

Seminar Speaker:

Hongzhang Shan
Future Technologies Group
CRD, LBNL

Title:

Performance characteristics of the Cray X1 and their implications for application performance tuning

Abstract:

The growing gap between sustained and peak performance for full-scale complex scientific applications on conventional supercomputers is a major concern in high performance computing. The recently-released vector-based Cray X1 offers to bridge this gap for many demanding scientific applications. However, this unique architecture contains both data caches and multi-streaming processing units, and the optimal programming methodology is still under investigation. In this paper we investigate Cray X1 code optimization for a suite of computational kernels originally designed for superscalar processors. We first investigate the memory performance characteristics of the Cray X1 and determine the most influential performance factors. Then, we examine how to optimize applications that are well tuned on superscalar platforms for the Cray X1 using its performance characteristics as guidelines. Finally, we evaluate the different types of optimizations used and the effort for their implementation.

Sponsor of Seminar:

Brent Gorda

Scientific Computing

Contact Esmond G. Ng EGNg@lbl.gov