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Good article benchmarking KVM storage

Published by Jim Salter // October 12th, 2015


http://www.ilsistemista.net/index.php/virtualization/47-zfs-btrfs-xfs-ext4-and-lvm-with-kvm-a-storage-performance-comparison.html

Good stuff. Nice in-depth run of several different benchmarks for everything from fileserver to mailserver to database type usage. A bit thin on the ground for configuration, and probably no surprises here if you already read my KVM storage article from 2013, but it’s always nice to get completely independent confirmation.

The author’s hardware setup was surprisingly wimpy – an AMD Phenom II with only 8GB of RAM – which may explain part of why the advanced filesystems did even more relatively poorly than expected in his testing. (ZFS did fine, but it didn’t blow the doors off of everything else the way it did in my testing, which was on a machine with four times as much RAM onboard. And btrfs absolutely tanked, across the board, whereas in my experience it’s typically more of a case of “it does really well until it does really badly”.) It was also interesting and gratifying to me that this article tested on CentOS, where mine tested on Ubuntu. Not that I expected any tremendous changes, but it’s always nice to see things holding up across distributions!

Thank you for the article, Gionatan – your work is appreciated!

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