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UCX Networking Layer Adopted by Charm++, Accelerating Charm++ Performance by up to 85%

Press Release

Joint Effort by the UCF Consortium and Charmworks, Inc. Enables World-Leading Performance for Charm++ on High Performance Interconnect Technologies

International Supercomputing Conference - The Unified Communication Framework (UCF) Consortium, a collaboration between industry, laboratories, and academia to create production grade communication frameworks and open standards for data centric and high-performance applications, today announced that the Unified Communication X Framework (UCX), has just been adopted via a backend UCX network interface layer within Charm++, a parallel programming framework for scalable HPC applications. The new UCX layer is now available from the Charm++ GitHub repository. The UCX layer accelerates existing and future applications that use Charm++ as the framework for parallelism and load balancing over high-performance interconnect technologies. Charm++ is the parallel runtime used by the NAMD biomolecular simulation program, along with many computational science and engineering applications.

“We are very pleased to announce that Charmworks has adopted UCX as a networking layer for Charm++,” said UCF Consortium Chairman Jeff Kuehn of Los Alamos National Laboratory. “The UCX open source framework enables network and programming model innovations, and supports a variety of high-performance interconnect technologies – InfiniBand, Ethernet, shared memory, and proprietary options. We are looking forward to continued collaboration with Charmworks on further optimizations.”

“The new UCX layer provides our users with a high-performance communication layer,” said Laxmikant “Sanjay” Kale, CEO of Charmworks Inc. “Having a universal layer that performs on par with network-specific layers helps streamline our software stack.”

The joint effort between the UCF Consortium and Charmworks enabled the UCX layer to act as a foundation for the message-driven task-based programming model of Charm++, Adaptive MPI, and Charm4Py. Early performance benchmarks of the UCX network interface layer on EDR InfiniBand, demonstrated performance improvements up to 85% compared to the verbs layer and up to 64% compared to the MPI layer based on a commercial MPI implementation.

The UCX network interface layer can co-exist with, and potentially replace, several legacy network interface layers in the future to provide a consolidated and unified network interface layer optimized for the specific underlying communication hardware. This reduces the amount of code to be maintained and provides assurance of the best performance on target platforms.

The UCX layer is available today on the GitHub master branch of Charm++, and will be included in the upcoming v6.10 release of Charm++.

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About UCF

An open communication framework is an essential enabler of Co-Design, opening the opportunity for innovation and development of heterogeneous co-processing elements working together synergistically and seamlessly to achieve a robust and capable ecosystem for Exascale computing and beyond. The Unified Communication Framework Consortium is a collaboration between industry, laboratories, and academia to create production grade communication frameworks and open standards for data centric and high-performance applications.

About Charmworks, Inc.

Charmworks, Inc. is a company focused on providing software for parallel computing ranging from servers, clusters, cloud resources, and supercomputers. Its offerings are based on decades of research at the University of Illinois in Urbana-Champaign, and include Charm++, Adaptive MPI, and Charades, which support their signature features including automatic load balancing and fault tolerance.

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