Speculative reconvergence for improved SIMT efficiency
Speculative reconvergence for improved SIMT efficiency
复制标题
推测再收敛以提高 SIMT 效率
DOI:
10.1145/3368826.3377911
复制
发表时间:
2020
期刊:
影响因子:
--
通讯作者:
Olivier Giroux
中科院分区:
文献类型:
--
作者:
S. Damani;Daniel R. Johnson;M. Stephenson;S. Keckler;Eddie Q. Yan;Michael McKeown;Olivier Giroux
GPUs perform most efficiently when all threads in a warp execute the same sequence of instructions convergently. However, when threads in a warp encounter a divergent branch, the hardware serializes the execution of diverged paths. We consider a class of convergence opportunities wherein multiple threads are expected to eventually execute a given segment of code, but not all threads arrive at the same time, resulting in serialized duplicate execution of common code subsequences such as function calls and loop bodies. Our goal is to promote convergence by helping threads that execute common code arrive together before allowing execution to proceed. We propose a new user-guided compiler mechanism, Speculative Reconvergence, to help identify and exploit previously untapped convergence opportunities that increase SIMT efficiency and improve performance. For the set of workloads we study, we see improvements ranging from 10% to 3× in both SIMT efficiency and in performance.
影响因子:
3.5
作者:
Ma, CM;Li, JS;Brain, S
通讯作者:
Brain, S