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arXiv · 2102.03614

A Newcomer In The PGAS World -- UPC++ vs UPC: A Comparative Study

Jérémie Lagravière·Johannes Langguth·Martina Prugger·Phuong H. Ha·Xing Cai
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Abstract

A newcomer in the Partitioned Global Address Space (PGAS) 'world' has arrived in its version 1.0: Unified Parallel C++ (UPC++). UPC++ targets distributed data structures where communication is irregular or fine-grained. The key abstractions are global pointers, asynchronous programming via RPC, futures and promises. UPC++ API for moving non-contiguous data and handling memories with different optimal access methods resemble those used in modern C++. In this study we provide two kernels implemented in UPC++: a sparse-matrix vector multiplication (SpMV) as part of a Partial-Differential Equation solver, and an implementation of the Heat Equation on a 2D-domain. Code listings of these two kernels are available in the article in order to show the differences in programming style between UPC and UPC++. We provide a performance comparison between UPC and UPC++ using single-node, multi-node hardware and many-core hardware (Intel Xeon Phi Knight's Landing).

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Jérémie Lagravière, Johannes Langguth, Martina Prugger, Phuong H. Ha, Xing Cai. 2021-02-06. A Newcomer In The PGAS World -- UPC++ vs UPC: A Comparative Study. https://arxiv.org/abs/2102.03614

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