REPLAYING MEMORY TRANSACTIONS WHILE RESOLVING MEMORY ACCESS FAULTS

One embodiment of the present invention is a parallel processing unit (PPU) that includes one or more streaming multiprocessors (SMs) and implements a replay unit per SM. Upon detecting a page fault associated with a memory transaction issued by a particular SM, the corresponding replay unit causes the SM, but not any unaffected SMs, to cease issuing new memory transactions. The replay unit then stores the faulting memory transaction and any faulting in-flight memory transaction in a replay buffer. As page faults are resolved, the replay unit replays the memory transactions in the replay buffer-removing successful memory transactions from the replay buffer-until all of the stored memory transactions have successfully executed. Advantageously, the overall performance of the PPU is improved compared to conventional PPUs that, upon detecting a page fault, stop performing memory transactions across all SMs included in the PPU until the fault is resolved.