I should have pointed out that my NFS mounts were with rsize=4096 and
wsize=4096. Without that my NFS speed is horrifically slow. An 8MB
file takes about 25s to read. With the 4k parameters that goes down to
about 8.6s (on an unloaded ethernet). I get these bad speeds with both
3c509 and 3c590. Note that our NetworkAppliance fileserver uses 4k
blocks, so this might be a factor. Maybe this should be a separate
thread. Should I expect decent NFS performance with NFS 1k?
OK. If I mount NFS with the default 1k packet sizes, Linux SMP does not
lock up on me!!! This sounds like a big clue to the problem.
So, could some of you out there try my crash method (pulling the
ethernet wire during a big NFS read) after mounting with rsize=4096 and
wsize=4096? I'll bet you'll lock up Linux SMP!