High-performance and low-energy buffer mapping method for multiprocessor DSP systems

Abstract

When implementing digital signal processing (DSP) applications onto multiprocessor systems, one significant problem in the viewpoints of performance is the memory wall. In this paper, to help alleviate the memory wall problem, we propose a novel, high-performance buffer mapping policy for SDF-represented DSP applications on bus-based multiprocessor systems that support the shared-memory programming model. The proposed policy exploits the bank concurrency of the DRAM main memory system according to the analysis of hierarchical parallelism. Energy consumption is also a critical parameter, especially in battery-based embedded computing systems. In this paper, we apply a synchronization back-off scheme on the top of the proposed high-performance buffer mapping policy to reduce energy consumption. The energy saving is attained by minimizing the number of non-essential synchronization transactions. We measure throughput and energy consumption on both synthetic and real benchmarks. The simulation results show that the proposed buffer mapping policy is very useful in terms of performance, especially in memory-intensive applications where the total execution time of computational tasks is relatively small compared to that of memory operations. In addition, the proposed synchronization back-off scheme provides a reduction in the number of synchronization transactions without degrading performance, which results in system energy saving.