Title
Programming the Linpack benchmark for Roadrunner
Abstract
We describe the challenges and opportunities we encountered when developing a hybrid version of the Linpack benchmark for the Los Alamos National Laboratory Roadrunner supercomputing system, which combines traditional x86-64 host processors with IBM PowerXCell™ 8i accelerator processors. The challenges included determining the proper division of the host and accelerator roles in the computation, transfer of data between the host and accelerator memory domains, alignment of data for communication and computation, and data format differences between the two processors. We also describe our approach to modeling the performance of the hybrid system and compare our performance estimates to witnessed performance on the system at different scales and levels of memory consumption. Through careful attention to these issues, we have produced a hybrid version of the Linpack benchmark for the Roadrunner system that achieves 77.8% of peak performance on a single compute node and 74.6% of peak performance over the entire system, making this system the first to achieve a Linpack result exceeding one petaflops (1015 floating-point operations per second).
Year
DOI
Venue
2009
10.1147/JRD.2009.5429075
IBM Journal of Research and Development
Field
DocType
Volume
IBM,Data format,Supercomputer,TOP500,Computer science,Parallel computing,Real-time computing,Roadrunner,Hybrid system,Computation
Journal
53
Issue
ISSN
Citations 
5
0018-8646
5
PageRank 
References 
Authors
0.82
12
4
Name
Order
Citations
PageRank
M. Kistler134332.54
John A. Gunnels271783.20
D. Brokenshire34913.51
B. Benton450.82