Multi-Clock Snapshot Isolation Concurrency Control for NVM Database

• DOI: 10.26599/tst.2021.9010036
• Publication Date: 2022-06-21T19:45:27Z
• Authors: Xuyang Liu; Kang Chen; Mengxing Liu; Shiyu Cai; Yongwei Wu; Weimin Zheng
• Keywords: Snapshot (computer storage)

Multi-Clock Snapshot Isolation (MCSI) is a concurrency control mechanism that implements snapshot isolation on single-layer Non-Volatile Memory (NVM) database. It stores single copy of data by using multi-version storage to ensure durability and runtime access. With multi-clock transaction timestamp assignment, MCSI can efficiently generate snapshots with vector clocks use per-thread status arrays identify uncommitted versions in NVM. For evaluation, we compared the PostgreSQL-style used NVM database N2DB. The maximum throughput 101%–195% higher than N2DB for YCSB workloads, 25%–49% TPC-C workloads. Moreover, latency remains relatively stable as thread count increases. 18 worker threads, average 65%–84% lower workloads 16%–43%