RS-store: A SkipList-Based Key-Value Store with Remote Direct Memory Access

Abstract

Many key-value stores use RDMA to optimize the messaging and data transmission between application layer and storage layer, most of which only provide point-wise operations. Skiplist-based store can support both point operations and range queries, but its CPU-intensive access operations combined with the high-speed network will easily lead to the storage layer reaches CPU bottlenecks. In this paper, we present RS-store, a skiplist-based key-value store with RDMA, which can overcome the cpu handle of the storage layer by enabling two access modes: local access and remote access. In RS-store, we redesign a novel data structure R-skiplist to save the communication cost in remote access, and implement a latch-free concurrency control mechanism to ensure all the concurrency during two access modes. At last, our evaluation on a RDMA-capable cluster shows that the performance of RS-store over R-skiplist is 0.6 –1 higher than the existing skiplist, and it supports application layer’s high scalability.