PGASUS: A Framework for C++ Application Development on NUMA Architectures

For the implementation of data-intensive C++ applications for cache coherent Non-Uniform Memory Access (NUMA) systems, both massive parallelism and data locality have to be considered. While massive parallelism has been largely understood, the shared memory paradigm is still deeply entrenched in the mindset of many C++ software developers. Hence, data locality aspects of NUMA systems have been widely neglected thus far. At first sight, applying shared nothing approaches might seem like a viable workaround to address locality. However, we argue that developers should be enabled to address locality without having to surrender the advantages of the shared address space of cache coherent NUMA systems. Based on an extensive review of parallel programming languages and frameworks, we propose a programming model specialized for NUMA-aware C++ development that incorporates essential mechanisms for parallelism and data locality. We suggest that these mechanisms should be used to implement specialized data structures and algorithm templates which encapsulate locality, data distribution, and implicit data parallelism. We present an implementation of the proposed programming model in the form of a C++ framework. To demonstrate the applicability of our programming model, we implement a prototypical application on top of this framework and evaluate its performance.