A Distributed Interleaving Scheme for Efficient Access to WideIO DRAM Memory

Achieving the main memory (DRAM) required bandwidth at ac- ceptable power levels for current and future applications is a ma- jor challenge for System-on-Chip designers for mobile platforms. Three dimensional (3D) integration and 3D stacked DRAM mem- ories promise to provide a significant boost in bandwidth at low power levels by exploiting multiple channels and wide data inter- faces. In this paper, we address the problem of efficiently exploit- ing the multiple channels provided by standard (JEDEC’s WIDE- IO) 3D-stacked memories, to extract maximal effective bandwidth and minimize latency for main memory access. We propose a new distributed interleaved access method that leverages the on-chip in- terconnect to simplify the design and implementation of the DRAM controller, without impacting performance compared to traditional centralized implementations. We perform experiments on realis- tic workload for a mobile communication and multimedia platform and show that our proposed distributed interleaving memory access method improves the overall throughput while minimally impact- ing the performance of latency sensitive communication flows.