Xtream-fit: an energy-delay efficient data memory subsystem for embedded media processing

In this paper, we propose a novel special-purpose data memory subsystem, called Xtream-fit, aimed at achieving high-energy-delay efficiency for streaming media applications. A key novelty of Xtream-fit is that it exposes a single customization parameter, thus enabling a very simple and yet effective design space exploration methodology. A second key contribution of this work is the ability to achieve very high energy-delay efficiency through a synergistic combination of: (1) special purpose memory subsystem components, namely, a streaming memory and scratch-pad memory; and (2) a novel task-based execution model that exposes/enhances opportunities for efficient prefetching and aggressive dynamic energy conservation techniques targeting on-chip and off-chip memory components. Extensive experimental results show that Xtream-fit reduces energy-delay product by 46% to 83%, as compared to general-purpose memory subsystems enhanced with state of the art cache decay and SDRAM power mode control policies.