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arXiv · 2010.12734

REMIX: Efficient Range Query for LSM-trees

Wenshao Zhong·Chen Chen·Xingbo Wu·Song Jiang
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Abstract

LSM-tree based key-value (KV) stores organize data in a multi-level structure for high-speed writes. Range queries on traditional LSM-trees must seek and sort-merge data from multiple table files on the fly, which is expensive and often leads to mediocre read performance. To improve range query efficiency on LSM-trees, we introduce a space-efficient KV index data structure, named REMIX, that records a globally sorted view of KV data spanning multiple table files. A range query on multiple REMIX-indexed data files can quickly locate the target key using a binary search, and retrieve subsequent keys in sorted order without key comparisons. We build RemixDB, an LSM-tree based KV-store that adopts a write-efficient compaction strategy and employs REMIXes for fast point and range queries. Experimental results show that REMIXes can substantially improve range query performance in a write-optimized LSM-tree based KV-store.

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Wenshao Zhong, Chen Chen, Xingbo Wu, Song Jiang. 2020-10-24. REMIX: Efficient Range Query for LSM-trees. https://arxiv.org/abs/2010.12734

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