Experimental Physics and
Industrial Control System

Andrew Johnson <[email protected]> · Wed, 26 Oct 2005 16:16:30 -0500

Hi Geoff,
Geoff Savage wrote:

We have encountered an issue with an mv162lx running vxworks 5.3.1 when
writing to a file via nfs. Every 10 seconds everything stops for 5
seconds. It appears that this is related to the network driver. The
suggested solution was to set the ethernet connection to half duplex
on the switch. Is this the only solution? The best solution?

I don't think the if_ei driver can use anything other than half duplex,
so I suspect that's what you're getting anyway. Have you run ifShow on
both sides of a transfer and examined the differences in values?
Could this be anything to do with discarded packets? NFS is prone to
delays if packets are lost, and this might be the issue.
If so, try increasing the number of receive and transmit frame
descriptors that the ei interface is initialized with. I believe you do
that by editing the file target/src/config/usrNetwork.c and change the
two "0" parameters in the #ifdef INCLUDE_EI section, which are
described in the vxWorks manual under if_ei(1). I don't know what the
defaults are for these that are used when you supply zeros, but in
Tornado 2.x we use 32 tfds and 128 rfds here - experiment and see if
this makes any difference.
HTH,
- Andrew
--
English probably arose from Normans trying to pick up Saxon girls.

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System