June 22–26, 2014
Leipzig, Germany

Presentation Details

Name: Orthrus: A Framework for Implementing Efficient Collective I/O in Multicore Clusters
Time: Wednesday, June 25, 2014
03:45 pm - 04:15 pm
Room:   Hall 3
CCL - Congress Center Leipzig
Breaks:04:15 pm - 05:15 pm Coffee Break
Speaker:   Song Jiang, Wayne State University
Abstract:   Optimization of access patterns using collective I/O imposes the overhead of exchanging data between processes. In a multi-core-based cluster the costs of inter-node and intra-node data communication are vastly different, and heterogeneity in the effciency of data-exchange poses both a challenge and opportunity for implementing effcient collective I/O. The opportunity is
to effectively exploit fast intra-node communication. We propose to improve communication locality for greater data exchange eciency. However, such an effort is at odds with improving access locality for I/O effciency, which can also be critical to collective-I/O performance. To address this issue we propose a framework, Orthrus, that can accommodate multiple collective-I/O implementations, each optimized for some performance aspects, and dynamically select the best performing one accordingly to current workload and system patterns. We have implemented Orthrus in the ROMIO library. Our experimental results with representative MPI-IO benchmarks on both a small dedicated cluster and a large production HPC system show that Orthrus can significantly improve collective I/O's performance under various workloads and system scenarios.

Xuechen Zhang, Georgia Institute of Technology; Jianqiang Ou, Wayne State University; Kei Davis, Los Alamos National Laboratory; Song Jiang, Wayne State University