adrift in the sea of experience

Wednesday, June 23, 2010

ZFS-Fuse reliability report

A few weeks ago, I got this question in the comments on my last NAS post:
Since you've been using ZFS-fuse for a time now, can you report here or blog about its stability? Has the daemon crashed on you, while taking a snapshot, or while "scrub"-ing?

How much data have you passed in?

First, note that the version of ZFS-FUSE which I am using is not a particular release, but this revision from the official git repository. I have not bothered to update my ZFS binaries since January, because I didn't encounter any problems.

The "zfs list" output for my pool shows that I am using 352 GiB. The pool consists of two 465 GiB disks in a mirror setup.
nas-pool           352G   105G    24K  /nas-pool
nas-pool/archive   118G   105G  71.1G  /nas-pool/archive
nas-pool/bulk      234G   105G   228G  /nas-pool/bulk

The pool is scrubbed by a cron script each sunday night. I have not seen any crashes/hangs during scrubbing. The scrubs have not detected any errors so far.

"archive" is snapshotted every night. "bulk" is snapshotted" only on sunday nights. The pool contains more than a hundred snapshots. Again, I have not seen any crashes or hangs.

Then there is read/write activity: I use it to automatically archive my emails from Gmail (nightly), sync with my dropbox folder (continuously), and to store my mp3s, photos, videos, downloads and backups when I need to. When reading or writing NAS files, I am usually working from my laptop over WiFi which is a speed bottleneck, so this probably doesn't really stress the file system. On the other hand, I do regularly make a full off-line backup of the "archive" filesystem by hooking up an external USB disk to the NAS. I haven't seen ZFS crash during any of this.

From this, I conclude that ZFS-Fuse is pretty stable.