InnerCache: A Tactful Cache Mechanism for RDMA-Based Key-Value Store

Abstract

High-Performance network technology, Remote Direct Memory Access (RDMA), has revealed its tremendous advantage over traditional TCP/IP. With its ultra-low latency and high bandwidth, RDMA has been extensively adopted in distributed environment, especially for in-memory key-value stores. However, although RDMA does provide the ability to interact with remote user space memory directly, memory copy still exists between data memory area and communication memory area with two-sided communication semantics in in-memory key-value store. In addition, using high performance one-sided communication semantics will expose memory totally, hence an inadvertent corrupt data operation could crash system. In this paper, we propose a tactful cache mechanism for RDMA-based in-memory key-value store -- InnerCache. Our design concerns two dimensions with respect to improve the system performance with two-sided communication semantics and make system less vulnerable. It merges one-sided and two-sided communication model through making communication memory cacheable. Experimental results show that InnerCache can efficiently improve the performance of RDMA-based in-memory key-value store.