HPX - The C++ Standard Library for Parallelism and Concurrency

Abstract

The new challenges presented by exascale system architectures have resulted in difficulty achieving the desired scalability using traditional distributed-memory runtimes. Asynchronous many-task systems (AMT) are based on a new paradigm showing promise in addressing these challenges, providing application developers with a productive and performant approach to programming on next generation systems. HPX is a C++ Library for concurrency and parallelism that is developed by The STE||AR Group, an international group of collaborators working in the field of distributed and parallel programming (Heller, Diehl, Byerly, Biddiscombe, & Kaiser, 2017; Kaiser et al., n.d.; Tabbal, Anderson, Brodowicz, Kaiser, & Sterling, 2011). It is a runtime system written using modern C++ techniques that are linked as part of an application. HPX exposes extended services and functionalities supporting the implementation of parallel, concurrent, and distributed capabilities for applications in any domain; it has been used in scientific computing, gaming, finances, data mining, and other fields.

Domaine-Specific Runtime to Orchestrate Computation on Heterogeneous Platforms

“…They both came into existence to facilitate asynchronous execution in specific applications, and while Charm++ has expanded its reach and is used in several codes, Uintah's runtime has remained embedded within the primary applications that motivated its creation. Other more general purpose asynchronous runtimes that have found variable degree of success in HPC systems include HPX [10], StarPU [2], Legion [3], and several others. Except for Uintah, which is embedded, all the other systems subscribe to the idea of being transparent to the application programmer.…”

NLMech: Implementation of finite difference/meshfree discretization of nonlocal fracture models

“…NLMech relies on the following open source softwares: HPX (Kaiser et al, 2020), Blaze (Iglberger et al, 2012), Blaze_Iterative, Gmsh (Geuzaine & Remacle, 2009), VTK (Schroeder et al, 2004), and yaml-cpp. For details about the specific version, we refer to NLMech's documentation.…”

“…On modern supercomputers, many core architectures where the threads per computational node increase, it is more and more important to focus on the fine-grain parallelism with increasing cores per computational nodes. NLMech is based on the C++ standard library for parallelism and concurrency (HPX) (Kaiser et al, 2020). For more details on utilization of asynchronous many-task systems, we refer to Diehl et al (2020).…”

Productivity, performance, and portability for computational fluid dynamics applications

“…These libraries follow the design philosophy of the C++ Standard Template Library [39] -indeed, their specification and implementation is often considered as a precursor towards inclusion in the C++ STL. The largest such projects are Boost [40], Eigen [27], and focusing on the parallelism aspect is HPX [41]. While there are countless such libraries, here we focus on ones that also target performance portability.…”