OSDI '23

Currently Playing: OSDI '23 - Replicating Persistent Memory Key-Value Stores with Efficient RDMA Abstraction

OSDI '23 - Replicating Persistent Memory Key-Value Stores with Efficient RDMA Abstraction Qing Wang, Tsinghua University, Youyou Lu, Tsinghua University, Jing Wang, Tsinghua University, Jiwu Shu, Tsinghua University Combining persistent memory (PM) with RDMA is a promising approach to performant replicated distributed key-value stores (KVSs). However, existing replication approaches do not work well when applied to PM KVSs: 1) Using RPC induces software queueing and execution at backups, increasing request latency; 2) Using one-sided RDMA WRITE causes numerous streams of small PM writes, leading to severe device-level write amplification (DLWA) on PM.In this paper, we propose Rowan, an efficient RDMA abstraction to handle replication writes in PM KVSs; it aggregates massive concurrent remote writes from different servers, and lands these writes to PM in a sequential (thus low DLWA) and one-sided (thus low latency) manner. We realize Rowan with off-the-shelf RDMA NICs. Further, we build Rowan-KV, a log-structured PM KVS using Rowan for replication. Evaluation shows that under write-intensive workloads, compared with PM KVSs using RPC and RDMA WRITE for replication, Rowan-KV boosts throughput by 1.22× and 1.39× as well as lowers median PUT latency by 1.77× and 2.11×, respectively, while largely eliminating DLWA. View the full OSDI '23 program at https://www.usenix.org/conference/osdi23/technical-sessions