GRapid: A compilation and runtime framework for rapid prototyping of graph applications on many-core processors

Many applications use graphs to represent and analyze data, but the effective deployment of graph algorithms on many-core processors is still a challenge. Many-core devices offer higher peak performance than multi-core devices; however, many-core programming is still a specialized skill. While compilation and runtime frameworks for parallelizing graph applications on multi-core CPUs exist, there is still a need for comparable frameworks for many-core devices. We propose GRapid: a compilation and runtime framework that generates efficient parallel implementations of generic graph applications for multi-core CPUs, NVIDIA GPUs and Intel Xeon Phi. Applications are expressed using a platform-agnostic programming API. Our source-to-source compiler performs platform-specific code transformations and optimizations, handles data transfers between the host and the coprocessor, and generates several functionally-equivalent code variants for the target platform. Our runtime library provides an efficient dynamic memory management scheme for applications where the graph topology is modified during processing. We used the proposed framework to rapidly generate efficient implementations of four graph applications on different target processors. Such rapid prototyping and re-targeting capability has obvious programmability advantages, but it can also be used to quickly identify target processors that better match the application´s computational needs.