Memory Access Scheduling Based on Dynamic Multilevel Priority in Shared DRAM Systems

Interapplication interference at shared main memory severely degrades performance and increasing DRAM frequency calls for simple memory schedulers. Previous memory schedulers employ a per-application ranking scheme for high system performance or a per-group ranking scheme for low hardware cost, but few provide a balance. We propose DMPS, a memory scheduler based on dynamic multilevel priority. First, DMPS uses “memory occupancy” to measure interference quantitatively. Second, DMPS groups applications, favors latency-sensitive groups, and dynamically prioritizes applications by employing a per-level ranking scheme. The simulation results show that DMPS has 7.2% better system performance and 22% better fairness over FRFCFS at low hardware complexity and cost.