Parallel and High Performance Computing

11 Directive-based GPU programming

This chapter covers

• Selecting the best directive-based language for your GPU
• Using directives or pragmas to port your code to GPUs or other accelerator devices
• Optimizing the performance of your GPU application

There has been a scramble to establish standards for directive-based languages for programming for GPUs. The pre-eminent directive-based language, OpenMP, released in 1997, was the natural candidate to look to as an easier way to program GPUs. At that time, OpenMP was playing catchup and mainly focused on new CPU capabilities. To address GPU accessibility, in 2011, a small group of compiler vendors, (Cray, PGI and CAPS) along with NVIDIA as the GPU vendor, joined to release the OpenACC standard, providing ...