Energy-Delay Efficient Data Memory Subsystems
Anand Ramachandran, Margarida F. Jacome · 2005
Data memory subsystems play a key role in the energy-delay efficiency of streaming media applications. In this article, we present a novel special-purpose data memory subsystem, Xtream-Fit, and demonstrate how it achieves high energy-delay efficiency across a wide range of media devices, including systems concurrently executing multiple applications under synchronization constraints. The effectiveness of Xtream-Fit relies on both the use of on-chip software-controlled memories and a novel taskbased execution model. These features enable efficient data prefetching and aggressive dynamic energy conservation policies, targeting on-chip and off-chip memory components. A key additional advantage of Xtream-Fit with respect to traditional cache-based memory subsystems is that it exposes a single customization parameter per application, thus enabling a very simple yet effective tuning methodology. We present extensive experimental results, empirically demonstrating that Xtream-Fit reduces energy-delay products by 43‐72%, compared to general-purpose memory subsystems enhanced with state-of-the-art cache-decay and SDRAM power-mode control policies.