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arXiv · 2003.04150

Lightweight Inter-transaction Caching with Precise Clocks and Dynamic Self-invalidation

Pulkit A. Misra·Srihari Radhakrishnan·Jeffrey S. Chase·Johannes Gehrke·Alvin R. Lebeck
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Abstract

Distributed, transactional storage systems scale by sharding data across servers. However, workload-induced hotspots result in contention, leading to higher abort rates and performance degradation. We present KAIROS, a transactional key-value storage system that leverages client-side inter-transaction caching and sharded transaction validation to balance the dynamic load and alleviate workload-induced hotspots in the system. KAIROS utilizes precise synchronized clocks to implement self-invalidating leases for cache consistency and avoids the overhead and potential hotspots due to maintaining sharing lists or sending invalidations. Experiments show that inter-transaction caching alone provides 2.35x the throughput of a baseline system with only intra-transaction caching; adding sharded validation further improves the throughput by a factor of 3.1 over baseline. We also show that lease-based caching can operate at a 30% higher scale while providing 1.46x the throughput of the state-of-the-art explicit invalidation-based caching.

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Pulkit A. Misra, Srihari Radhakrishnan, Jeffrey S. Chase, Johannes Gehrke, Alvin R. Lebeck. 2020-03-09. Lightweight Inter-transaction Caching with Precise Clocks and Dynamic Self-invalidation. https://arxiv.org/abs/2003.04150

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