Dynamic Partitioned Global Address Spaces for power efficient DRAM virtualization
Jeffrey Young, Sudhakar Yalamanchili · International Conference on Green Computing · 2010
Dynamic Partitioned Global Address Spaces (DPGAS) is an abstraction that allows for quick and efficient remapping of physical memory addresses within a global address space, enabling more efficient sharing of remote DRAM. While past work has proposed several uses for DPGAS [1], the most pressing issue in today's data centers is reducing power. This work uses a detailed simulation infrastructure to study the effects of using DPGAS to reduce overall data center power through low-latency accesses to “virtual” DIMMs. Virtual DIMMs are remote DIMMs that can be mapped into a local node's address space using existing operating system abstractions and low-level hardware support to abstract the DIMM's location from the application using it. By using a simple spill-receive memory allocation model, we show that DPGAS can reduce memory power from 18% to 49% with a hardware latency of 1 to 2 μs in typical usage scenarios. Additionally, we demonstrate the range of scenarios where DPGAS can be realized over a shared 10 Gbps Ethernet link with normal network traffic.