SkelCL – A Portable Multi-GPU Skeleton Library

Modern Graphics Processing Units (GPU) are increasingly used as general-purpose processors. While the two currently most widely used programming models for GPUs, CUDA and OpenCL, are a step ahead as compared to ex-tremely laborious shader programming, they still remain effort-demanding and error-prone. Memory management is complex due to the separate memories of CPU and GPU and GPUs support only a subset of common CPU programming languages. Both, CUDA and OpenCL lack support for multi-GPU systems, such that additional challenges like communication and synchronization arise when using multiple GPUs. We present SkelCL – a novel library for simplifying OpenCL programming of single and multiple GPUs. SkelCL provides for the application programmer two main abstractions: Firstly, a unified memory management that implicitly transfers data transfers between the system’s and the GPU’s memory. Lazy copying techniques pre