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arXiv · 2211.11818

Node-Type-Based Load-Balancing Routing for Parallel Generalized Fat-Trees

John Gliksberg·Jean-Noel Quintin·Pedro Javier Garcia
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Abstract

High-Performance Computing (HPC) clusters are made up of a variety of node types (usually compute, I/O, service, and GPGPU nodes) and applications don't use nodes of a different type the same way. Resulting communication patterns reflect organization of groups of nodes, and current optimal routing algorithms for all-to-all patterns will not always maximize performance for group-specific communications. Since application communication patterns are rarely available beforehand, we choose to rely on node types as a good guess for node usage. We provide a description of node type heterogeneity and analyse performance degradation caused by unlucky repartition of nodes of the same type. We provide an extension to routing algorithms for Parallel Generalized Fat-Tree topologies (PGFTs) which balances load amongst groups of nodes of the same type. We show how it removes these performance issues by comparing results in a variety of situations against corresponding classical algorithms.

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John Gliksberg, Jean-Noel Quintin, Pedro Javier Garcia. 2022-11-21. Node-Type-Based Load-Balancing Routing for Parallel Generalized Fat-Trees. https://doi.org/10.1109/hipineb.2018.00010

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