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arXiv · 2210.04179

Oze: Decentralized Graph-based Concurrency Control for Long-running Update Transactions (Extended Version)

Jun Nemoto·Takashi Kambayashi·Takashi Hoshino·Hideyuki Kawashima
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Abstract

This paper proposes Oze, a concurrency control protocol that handles heterogeneous workloads, including long-running update transactions. Oze explores a large scheduling space using a multi-version serialization graph to reduce false positives. Oze manages the graph in a decentralized manner to exploit many cores in modern servers. We further propose an OLTP benchmark, BoMB (Bill of Materials Benchmark), based on a use case in an actual manufacturing company. BoMB consists of one long-running update transaction and five short transactions that conflict with each other. Experiments using BoMB show that Oze can handle the long-running update transaction while achieving four orders of magnitude higher throughput than state-of-the-art optimistic and multi-version protocols and up to five times higher throughput than pessimistic protocols. We also show Oze performs comparably with existing techniques even in a typical OLTP workload, TPC-C, thanks to a protocol switching mechanism.

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Jun Nemoto, Takashi Kambayashi, Takashi Hoshino, Hideyuki Kawashima. 2025-08-06. Oze: Decentralized Graph-based Concurrency Control for Long-running Update Transactions (Extended Version). https://doi.org/10.14778/3742728.3742730

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