[OpenAFS] openafs fileserver running on drbd?

Joe Buehler jbuehler@spirentcom.com
Wed, 06 Dec 2006 08:07:27 -0500

Is anyone running an AFS file server on top of drbd?  We have been
attempting this without very satisfactory results -- the performance
and stability are not good.

The two machines involved are:

- linked with e1000 adapters and crossover cables
- use the 2.4.33 kernel
- use drbd 0.7.21
- use e1000 drivers 7.2.7
- OpenAFS 1.4.2

Looking at the drbd traffic with ethereal, I see something a little
odd -- the TCP round trip times are scattered all over the place, up
to a maximum of 40 milliseconds.

My initial suspicion is that this is due to fsync calls by the AFS
servers, but I haven't found any information yet on how drbd handles
fsync.  I have applied the fsync-reduction patch recently discussed
without much success.
Joe Buehler