Breadth First Search on APEnet+

Abstract

We present preliminary results of a multi-GPU code for exploring large graphs (hundreds of millions vertices and billions of edges) by using the Breadth First Search algorithm. The GPU hosts are connected by APEnet+, a custom interconnection network that has full support for NVIDIA GPUDirect peer-topeer communication, i.e. the technology allowing a third party device to directly access the GPU memory over the PCI express bus.