PMDB: A Range-Based Key-Value Store on Hybrid NVM-Storage Systems

Emerging Nov-Volatile Memory (NVM) may replace DRAM as main memory in future computers. However, data will likely still be stored on storage due to the enormous large size of available data. We investigate how key-value stores can be efficiently designed and implemented in a hybrid system, called NVM-Storage system, consisting of NVM as memory and traditional storage. We first discuss the performance trade-offs among Put, Get, and Range Query of the existing designs. Then, we propose PMDB, a range-based key-value store on NVM-Storage systems. PMDB achieves good performance for Put, Get and Range Query at the same time by utilizing a range-based data management and deploying a light-weight index on NVM. We compare PMDB with the state-of-the-art schemes including SLM-DB [21] and MatrixKV [40] for hybrid NVM-storage systems. Evaluation results indicate that in workloads with mixed Put, Get and Range Queries, PMDB outperforms existing key-value stores by 1.16× - 2.49×.