Collective Framework and Performance Optimizations to Open MPI for Cray XT Platforms

Conference · Sat Jan 01 04:00:00 EST 2011

OSTI ID:1035529

Ladd, Joshua S ^[1]; Gorentla Venkata, Manjunath ^[1]; Shamis, Pavel ^[1]; Graham, Richard L ^[1]

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1. ORNL

The performance and scalability of collective operations plays a key role in the performance and scalability of many scientific applications. Within the Open MPI code base we have developed a general purpose hierarchical collective operations framework called Cheetah, and applied it at large scale on the Oak Ridge Leadership Computing Facility's Jaguar (OLCF) platform, obtaining better performance and scalability than the native MPI implementation. This paper discuss Cheetah's design and implementation, and optimizations to the framework for Cray XT 5 platforms. Our results show that the Cheetah's Broadcast and Barrier perform better than the native MPI implementation. For medium data, the Cheetah's Broadcast outperforms the native MPI implementation by 93% for 49,152 processes problem size. For small and large data, it out performs the native MPI implementation by 10% and 9%, respectively, at 24,576 processes problem size. The Cheetah's Barrier performs 10% better than the native MPI implementation for 12,288 processes problem size.

• Research Organization: Oak Ridge National Laboratory (ORNL)
• Sponsoring Organization: SC USDOE - Office of Science (SC)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1035529
• Country of Publication: United States
• Language: English

Related Subjects

99 GENERAL AND MISCELLANEOUS
COMPUTER CODES
COMPUTERS
DESIGN
IMPLEMENTATION
Open MPI Collectives Cray XT5 Portals
PERFORMANCE