IOPriority: To The Device and Beyond

Authors: 

Adam Manzanares, Filip Blagojevic, and Cyril Guyot, Western Digital Research

Abstract: 

In large scale data centers, controlling tail latencies of IO requests keeps storage performance bounded and predictable, which is critical for infrastructure resource planning. This work provides a transparent mechanism for applications to pass prioritized IO commands to storage devices. As a consequence, we observe much shorter tail latencies for prioritized IO while impacting nonprioritized IO in a reasonable manner. We also provide a detailed description of the changes we made to the Linux Kernel that enable applications to pass IO priorities to a storage device. Our results show that passing priorities to the storage device is capable of decreasing tail latencies by a factor of 10x while decreasing IOPS minimally.

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BibTeX
@inproceedings {203368,
author = {Adam Manzanares and Filip Blagojevi{\'c} and Cyril Guyot},
title = {IOPriority: To The Device and Beyond},
booktitle = {9th {USENIX} Workshop on Hot Topics in Storage and File Systems (HotStorage 17)},
year = {2017},
address = {Santa Clara, CA},
url = {https://www.usenix.org/conference/hotstorage17/program/presentation/manzanares},
publisher = {{USENIX} Association},
}