Evolving Ext4 for Shingled Disks

Authors: 

Abutalib Aghayev, Carnegie Mellon University; Theodore Ts’o, Google, Inc.; Garth Gibson, Carnegie Mellon University; Peter Desnoyers, Northeastern University

Note: Due to technical difficulties, there is no audio of this talk.

Abstract: 

Drive-Managed SMR (ShingledMagnetic Recording) disks offer a plug-compatible higher-capacity replacement for conventional disks. For non-sequential workloads, these disks show bimodal behavior: After a short period of high throughput they enter a continuous period of low throughput.

We introduce ext4-lazy1, a small change to the Linux ext4 file system that significantly improves the throughput in both modes. We present benchmarks on four different drive-managed SMR disks from two vendors, showing that ext4-lazy achieves 1.7-5.4x improvement over ext4 on a metadata-light file server benchmark. On metadata-heavy benchmarks it achieves 2-13x improvement over ext4 on drive-managed SMR disks as well as on conventional disks.

Open Access Media

USENIX is committed to Open Access to the research presented at our events. Papers and proceedings are freely available to everyone once the event begins. Any video, audio, and/or slides that are posted after the event are also free and open to everyone. Support USENIX and our commitment to Open Access.

BibTeX
@inproceedings {202248,
author = {Abutalib Aghayev and Theodore Ts{\textquoteright}o and Garth Gibson and Peter Desnoyers},
title = {Evolving Ext4 for Shingled Disks},
booktitle = {15th USENIX Conference on File and Storage Technologies (FAST 17)},
year = {2017},
isbn = {978-1-931971-36-2105},
address = {Santa Clara, CA},
pages = {105--120},
url = {https://www.usenix.org/conference/fast17/technical-sessions/presentation/aghayev},
publisher = {USENIX Association},
month = feb
}