SMRDB: Key-Value Data Store for Shingled Magnetic Recording Disks

Appeared in Proceedings of SYSTOR 2015. Won Best Paper award.

Abstract

Shingled Magnetic Recording (SMR) disks employ a shingled write process that overlaps the data tracks on the disk surface like the shingles on a roof, thereby increasing disk areal density with minimal manufacturing changes. While these disks have the same read behavior as current disks, random writes and in-place data updates are no longer possible, since a write to a track must overwrite and destroy data on all tracks that it overlaps. Given this change in write behavior, we argue that the best way to utilize these disks is not by masquerading them as traditional disks, but by using approaches that leverage their proclivity for sequential writes. To address this need, we developed SMRDB, a key-value data store for SMR disks, demonstrating that SMR disks can be effectively used to replace conventional disks for many applications. We evaluate SMRDB against a state-of-the-art LSM-tree based key-value database engine, LevelDB, on conventional disks. Our Yahoo! Cloud Serving Benchmark results show that, de- spite being restricted to sequential writes, SMRDB outperforms LevelDB by 8.8–123.6%.

Publication date:
May 2015

Authors:
Rekha Pitchumani
James Hughes
Ethan L. Miller

Projects:
Shingled Disk

Available media

Full paper text: PDF

Bibtex entry

@inproceedings{pitchumani-systor15,
  author       = {Rekha Pitchumani and James Hughes and Ethan L. Miller},
  title        = {{SMRDB}: Key-Value Data Store for Shingled Magnetic Recording Disks},
  booktitle    = {Proceedings of SYSTOR 2015},
  month        = may,
  year         = {2015},
}