EEMARQ: Efficient Lock-Free Range Queries with Memory Reclamation

Gali Sheffi; Pedro Ramalhete; Erez Petrank

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arXiv · 2210.17086

EEMARQ: Efficient Lock-Free Range Queries with Memory Reclamation

Gali Sheffi·Pedro Ramalhete·Erez Petrank

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Abstract

Multi-Version Concurrency Control (MVCC) is a common mechanism for achieving linearizable range queries in database systems and concurrent data-structures. The core idea is to keep previous versions of nodes to serve range queries, while still providing atomic reads and updates. Existing concurrent data-structure implementations, that support linearizable range queries, are either slow, use locks, or rely on blocking reclamation schemes. We present EEMARQ, the first scheme that uses MVCC with lock-free memory reclamation to obtain a fully lock-free data-structure supporting linearizable inserts, deletes, contains, and range queries. Evaluation shows that EEMARQ outperforms existing solutions across most workloads, with lower space overhead and while providing full lock freedom.

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BibTeX RIS

Gali Sheffi, Pedro Ramalhete, Erez Petrank. 2022-10-31. EEMARQ: Efficient Lock-Free Range Queries with Memory Reclamation. https://arxiv.org/abs/2210.17086

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