Processing hanging under 4.0

[Roland Schneider]

Configuration:  Sun 4/280, SunOS 4.0 EXPORT  (eeserv)  [ mounts mymach files ]
                Sun 3/260, SunOS 3.5 EXPORT  (mymach)

Has anyone else run into a problem where processes on a 4/280 (eeserv)
which access files on a 3/260 (mymach) vi NFS hang in a disk wait ("D"
status in ps) and cannot coaxed back into operation or even killed.  This
seems to be happening with increasing frequency here, and is very annoying
as it requires rebooting the NFS client.  (the 4/280)  Other clients (sun
3's) of mymach continue working fine.

The problem is actually a little stranger than I described above.  Here is
a scenerio:  (my home directory is on mymach)

Script started on Sat Nov 12 11:01:33 1988
mymach% rlogin eeserv
Last login: Sat Nov 12 00:19:36 from mymach

eeserv% ls
chris		fool		nnet		sun_service		xxx
....

eeserv% cat xxx
... the contents of xxx ...
eeserv% cd fool
eeserv% ls
testfile
eeserv% cat testfile

===================================
At this point, cat is stuck in a disk wait, and will not die until the
system is rebooted.  So: I can log in, cat (or vi, etc) a file in my home
directory, do an "ls", change directories, do an "ls" here too, but not
access any files.  This seemed to be true for EVERY new process I started,
no matter if as root or not.  I also noticed this behavior on a 4/110 this
morning.  The process which was hung was on ttyp0, and guess what I ran
into?  The well known problem of windows dying on the first character
typed.  A coincidence?

I'd be interested in hearing from anyone else who has run into this,
especially if they've found a solution.  I have not been able to recreate
this problem on demand, but I suspect it begins during heavy NFS access.

Roland Schneider
Dept. Electrical Engineering
University of Manitoba
Winnipeg, Manitoba, Canada