VL-CDRAM: variable line sized cached DRAMs

Abstract

Many of the current memory architectures embed a SRAM cache within the DRAM memory. These architectures exploit a wide internal data bus to transfer an entire DRAM row to the on-memory cache. However, applications exhibit a varying spatial locality across the different DRAM rows that are accessed and buffering the entire row may be wasteful. In order to adapt to the changing spatial locality, we propose a variable line size cached DRAM (VL-CDRAM) that can buffer portions of an accessed DRAM row. Our evaluation shows that the proposed approach is effective in not only reducing the energy consumption but also in improving the performance across various memory configurations.