Bug#440676: nfs-kernel-server: Simultaneous transfer on mirrored nfs mounts causes service freezes
Actually, the incident is primarily on i386 machines. Sorry about the
report being a bit deceptive by submitting from my standard work machine
which is a powerpc. The powerpc kernel may not exhibit this behavior.
Moritz Mühlenhoff wrote:
Jeffrey B. Green wrote:
(I've delayed a few weeks in reporting this bug and so unsure whether other
work on it has already occurred. However I could not find anything
A very similar behaviour can be reproduced with i386 as well (with the Etch
versions of the Linux kernel and nfs-kernel-server):
We have a setup where a block device is replicated with drbd. On this device
an ext3 partition has been created, which is exported over NFS. Reading from
the NFS share works fairly well, however concurrent writes to the share lead
to lockups. The client processes copying data to the share are stalling and
sometimes the system is locked up requiring a hard reboot.
This is reproducable with both NFS over UDP and NFS over TCP.
I originally assumed this was only triggerable with the block dev on a drbd
device, but per Jeffrey's mail is seems to be a more widespread problem.