[OpenAFS] Poor performance on new ZFS-based file server
Wed, 11 Jul 2007 18:49:46 -0500
I've been getting intermittant reports of slow read performance on a new
AFS file server that I recently set up based on ZFS. It is using locally
attached disks in a RAID-Z2 (double parity) configuration. I was wondering
if anyone might be able to provide any ideas for tuning / investigating
the problem. The slow performance that's been reported seems to be against
a RW volume with no replicas.
Right now, I am using OpenAFS 1.4.4 with the "no fsync" patch. The
options I'm using for the fileserver are "-nojumbo" and "-nofsync".
I've also set the ZFS parameters "atime" to "off" and "recordsize"
to "64K" as recommended in Dale Ghent's presentation at the OpenAFS
There are a bunch of file server options that I'm not sure if they would
help or not. Any advice would be appreciated as I'm looking at ZFS-based
file servers for some new file servers I'm setting up, but my experience
so far has been mostly with the OpenAFS 1.2 inode-based file server.
Brian Sebby (email@example.com) | Unix and Operation Services
Phone: +1 630.252.9935 | Computing and Information Systems
Fax: +1 630.252.4601 | Argonne National Laboratory