Building Heterogeneous Unified Virtual Memories (UVMs) without the Overhead

作者：Koukos Konstantinos^*; Ros Alberto^*; Hagersten Erik^*; Kaxiras Stefanos^*

来源：ACM Transactions on Architecture and Code Optimization, 2016, 13(1): 1.

DOI：10.1145/2889488

• Multicore
• heterogeneous coherence
• GPU MMU design
• virtual coherence protocol
• directory-less protocol

This work proposes a novel scheme to facilitate heterogeneous systems with unified virtual memory. Research proposals implement coherence protocols for sequential consistency (SC) between central processing unit (CPU) cores and between devices. Such mechanisms introduce severe bottlenecks in the system; therefore, we adopt the heterogeneous-race-free (HRF) memory model. The use of HRF simplifies the coherency protocol and the graphics processing unit (GPU) memory management unit (MMU). Our protocol optimizes CPU and GPU demands separately, with the GPU part being simpler while the CPU is more elaborate and latency aware. We achieve an average 45% speedup and 45% electronic data processing reduction (20% energy) over the corresponding SC implementation.

• 出版日期2016-4