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arXiv · 2504.17598

TSUE: A Two-Stage Data Update Method for an Erasure Coded Cluster File System

Zheng Wei·Jing Xing·Yida Gu·Wenjing Huang·Dong Dai·Guangming Tan·Dingwen Tao
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Abstract

Compared to replication-based storage systems, erasure-coded storage incurs significantly higher overhead during data updates. To address this issue, various parity logging methods have been pro- posed. Nevertheless, due to the long update path and substantial amount of random I/O involved in erasure code update processes, the resulting long latency and low throughput often fail to meet the requirements of high performance applications. To this end, we propose a two-stage data update method called TSUE. TSUE divides the update process into a synchronous stage that records updates in a data log, and an asynchronous stage that recycles the log in real-time. TSUE effectively reduces update latency by transforming random I/O into sequential I/O, and it significantly reduces recycle overhead by utilizing a three-layer log and the spatio-temporal locality of access patterns. In SSDs cluster, TSUE significantly im- proves update performance, achieving improvements of 7.6X under Ali-Cloud trace, 5X under Ten-Cloud trace, while it also extends the SSD's lifespan by up to 13X through reducing the frequencies of reads/writes and of erase operations.

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Zheng Wei, Jing Xing, Yida Gu, Wenjing Huang, Dong Dai, Guangming Tan, Dingwen Tao. 2025-04-24. TSUE: A Two-Stage Data Update Method for an Erasure Coded Cluster File System. https://doi.org/10.1145/3731545.3731577

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