I'm bringing up a new BSP under vxWorks 5.5.1 MIPS64 (actually just a
port of of vxWorks 5.3.1 BSP to 5.5.1. This is a MIPS RM7000 custom
board. The same exact board is working find under 5.3.1)

I am seeing very slow shared memory network transfers (rlogins across
the backplane, if they complete at all, took from seconds to minutes to
echo typing). Note that this is all happening without any application
software running.

I tried swithing th SM_TAS_SOFT and SM_POLL to eliminate as much of the
BSP as possible and got the same behaviour.

I turned on all of the smVerbose flags and did some simple pings. What I
see is odd. If board A pings board B and it works I see (in board B with
the verbose flags) the smpacket coming in and going out.

When it fails, I see the packet coming in, but nothing going out (again
based on the verbose flags).

Ethernet interfaces continue to operate normally with no dropped packet

It appears like the network stack is dropping the packets internally or
randomly trying to route them someplace else.

Anyone else ever see anything like this? Any thoughts?