[vortex] 3c905 hanging when network load is high

[Bogdan Costescu]

On Sat, 12 Jan 2002, Markus Schaub wrote:

> But in my mind, it should go away automatically in this case, as the
> disk doesn't generate any more interrupts when the network is slow?

When the transmit timeout occurs, a full ring is normally sent. This might 
in turn generate another burst of interrupts when again one or more 
interrupts might get lost...
Loosing interrupts situations are generally hard to diagnose. Bringing the 
interface "down" then "up" dissasociates then associates again the 
interrupt handler; this clears up interrupt status.

> I was't able to reproduce the error by copying files from the server
> to another machine. So how can I copy a file from the client to
> /dev/null on the server via NFS?

client> mount -t nfs server:/dir /mnt/servdir
client> time dd if=/mnt/servdir/bigfile of=/dev/null

which will test capacity of receiving of the client, and

client> mount -t nfs server:/dir /mnt/servdir
client> time dd if=/dev/zero of=/mnt/servdir/bigfile bs=4096k count=8

which will test capacity of sending of the client.

It's not possible to write to /dev/null on the server with this setup. If 
you want to do this, you'll have to turn the server into a NFS client 
(and the client into a NFS server) and then repeat the above procedure.
-- 
Bogdan Costescu

IWR - Interdisziplinaeres Zentrum fuer Wissenschaftliches Rechnen
Universitaet Heidelberg, INF 368, D-69120 Heidelberg, GERMANY
Telephone: +49 6221 54 8869, Telefax: +49 6221 54 8868
E-mail: Bogdan.Costescu@IWR.Uni-Heidelberg.De