MemcachedGPU: scaling-up scale-out key-value stores

Abstract

This paper tackles the challenges of obtaining more efficient data center computing while maintaining low latency, low cost, programmability, and the potential for workload consolidation. We introduce GNoM, a software framework enabling energy-efficient, latency bandwidth optimized UDP network and application processing on GPUs. GNoM handles the data movement and task management to facilitate the development of high-throughput UDP network services on GPUs. We use GNoM to develop MemcachedGPU, an accelerated key-value store, and evaluate the full system on contemporary hardware. MemcachedGPU achieves ~10 GbE line-rate processing of ~13 million requests per second (MRPS) while delivering an efficiency of 62 thousand RPS per Watt (KRPS/W) on a high-performance GPU and 84.8 KRPS/W on a low-power GPU. This closely matches the throughput of an optimized FPGA implementation while providing up to 79% of the energy-efficiency on the low-power GPU. Additionally, the low-power GPU can potentially improve cost-efficiency (KRPS/$) up to 17% over a state-of-the-art CPU implementation. At 8 MRPS, MemcachedGPU achieves a 95-percentile RTT latency under 300μs on both GPUs. An offline limit study on the low-power GPU suggests that MemcachedGPU may continue scaling throughput and energy-efficiency up to 28.5 MRPS and 127 KRPS/W respectively.