ViPZonE: OS-Level Memory Variability-Driven Physical Address Zoning for Energy Savings

ITRS predicts that over the next decade, hardware power variation will increase at alarming rates. As a result, design-ers must build software that can adapt to and exploit these variations to reduce power consumption and improve system performance. This paper presents ViPZonE, a system-level solution that opportunistically exploits DRAM power vari-ation through physical address zoning. ViPZonE is com-posed of a variability-aware software stack that allows de-velopers to indicate to the OS the expected dominant us-age patterns (write or read) as well as level of utilization (high, medium, or low) through high-level APIs. ViPZonE’s variability-aware page allocator, implemented in the Linux kernel, is responsible for interpreting these high-level requests for memory and transparently mapping them to physical ad-dress zones with different power consumption. Our experi-mental results across various configurations running PAR-SEC workloads show an average of 13.1 % memory power consumption savings at the cost of a modest 1.03 % increase in execution time over a typical Linux virtual memory allo-cator