Experimental Physics and
Industrial Control System

"Steven M. Hartman" <[email protected]> · Thu, 30 Sep 2010 14:20:12 -0400

Matthias Clausen wrote:
Good idea - we got a hint from the hardware vendor that there might be a
vxWorks 6.7 "SMP Perfomance Patch" which should solve 'similar'
problems. - We'll check with WRS.

Strange enough that they did not mention this to us...

2) Also look for vxWorks 6 patches which could be installed.

Hello Matthias--
The "Page Fault Addr : 0x00000000" looks very suspicious. Null
pointer somewhere? Strange that is is occurring in what looks to
be deep within tNetTask.
I would second the suggestion to apply recommended patches for
6.7. We started putting VxWorks 6.7 into production during our
summer maintenance period (~8 IOCs so far), so the longest running
production IOC with this version is less then 2 months uptime. But
we have not seen any such problems in testing or production. We do
have all WRS recommended patches as of July 9 (from trying to
debug a geiEnd driver problem for the mv5500, fixed in 6.8 by the
way).
Unfortunately all of the network diagnostics do not work after a crash
of the net task.

The shell will be blocked and no more diagnostics are possible.

We saw this before with 5.5 and it does make it very difficult to
debug. In our case, memory corruption was occurring from another
task writing beyond a malloc'd buffer, clobbering the meta data
and making a mess of the free list. That task would end up
suspended during either a malloc or free, so it ended up holding
the semaphore protecting malloc/free. Apparently, tnetTask (at
least in 5.5) does lots of malloc/free so we would find the
suspended task promoted to priority 50 with tnetTask waiting on it
to get the semaphore (and thus no network). The console shell
would work, but a number of the show routines also use malloc. If
you use any of those, the shell ends up blocking on the same
semaphore and your only option is a reboot.
Does 'i' show anything promoted to a higher priority for you?

--
Steven Hartman
[email protected] || 865-466-6473

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System