Performance Characterization and Optimization of Atomic Operations on AMD GPUs

—Atomic operations are important building blocks in supporting general-purpose computing on graphics processing units (GPUs). For instance, they can be used to coordinate execution between concurrent threads, and in turn, assist in constructing complex data structures such as hash tables or implementing GPU-wide barrier synchronization. While the performance of atomic operations has improved substantially on the latest NVIDIA Fermi-based GPUs, system-provided atomic operations still incur significant performance penalties on AMD GPUs. A memory-bound kernel on an AMD GPU, for example, can suffer severe performance degradation when including an atomic operation, even if the atomic operation is never executed. In this paper, we first quantify the performance impact of atomic instructions to application kernels on AMD GPUs. We then propose a novel software-based implementation of atomic operations that can significantly improve the overall kernel performance. We evaluate its performan...

• Type: Journal
• Year: 2011
• Where: CLUSTER
• Authors: Marwa Elteir, Heshan Lin, Wu-chun Feng
• Keywords: Application Kernel, Application Kernels, CLUSTER 2011, Distributed And Parallel Computing, Micro Benchmarks