Warp size impact in GPUs
Ahmad Lashgar, Amirali Baniasadi, Ahmad Khonsari · 2013
There are a number of design decisions that impact a GPU's performance. Among such decisions deciding the right warp size can deeply influence the rest of the design. Small warps reduce the performance penalty associated with branch divergence at the expense of a reduction in memory coalescing. Large warps enhance memory coalescing significantly but also increase branch divergence. This leaves designers with two choices: use small warps and invest in finding new solutions to enhance coalescing or use large warps and address branch divergence employing effective control-flow solutions.