@inproceedings{ba650bebb34a44e0918cb643bb72f591,
title = "Lifetime-leveling LSM-tree compaction for ZNS SSD",
abstract = "The Log-Structured Merge (LSM) tree is considered well-suited to zoned namespace (ZNS) storage devices since the write requests to LSM-tree is sequential. However, zones can be partially invalidated and be fragmented during LSM-tree compaction. The partially-invalid zones cannot be utilized and thus space amplification becomes significant. To reclaim the invalid space, host-managed garbage collection (GC) is required, which increases the write amplification of ZNS storage and degrades I/O performance. We introduce a lifetime-leveling compaction (LL-compaction) tailored for ZNS SSD, which can alleviate space amplification without GC by making the sorted string tables in a zone have similar lifetimes. In our experiments using LevelDB, the LL-compaction achieved 1.7x better performance by removing GCs.",
keywords = "compaction, LSM-tree, solid-state drives, zoned namespace",
author = "Jeeyoon Jung and Dongkun Shin",
note = "Publisher Copyright: {\textcopyright} 2022 ACM.; 14th ACM Workshop on Hot Topics in Storage and File Systems, HotStorage 2022 ; Conference date: 27-06-2022 Through 28-06-2022",
year = "2022",
month = jun,
day = "27",
doi = "10.1145/3538643.3539741",
language = "English",
series = "HotStorage 2022 - Proceedings of the 2022 14th ACM Workshop on Hot Topics in Storage and File Systems",
publisher = "Association for Computing Machinery, Inc",
pages = "100--105",
booktitle = "HotStorage 2022 - Proceedings of the 2022 14th ACM Workshop on Hot Topics in Storage and File Systems",
}