Re: panic: m_copym, length > size of mbuf chain

From: Daniel Lang <dl_at_leo.org>
Date: Wed, 7 Jul 2004 19:40:44 +0200
Hi Robert,

Robert Watson wrote on Wed, Jul 07, 2004 at 12:24:59PM -0400:
[..]
> > As I told Bruce, I have never set debug.mpsafenet (in case you are
> > especially interested in this tunable). 
> 
> Yeah, that's one of the ones I was particularly interested in :-).
> 
> Just to try ruling out possibilities -- have you run an extensive set of
> hardware diagnostics?  Most server class hardware ships with a decent
> diagnostics disk, and I'm sure we can find some for you in the event your
> hardware didn't come with some.  While it's quite possibly a software

I agree. I have indeed have asked our hardware department to check
the memory. They did run memtest86 several days without any error,
so I am somewhat convinced, that the memory is intact. It is Dell
memory, ordered just for this server, so I assume the specs match
the requirements.

However, it is obviously possible, that other system components could
be faulty. I did follow your advice and downloaded a set of diagnostic
utilities for this server from the Dell support page. I will execute them
tomorrow, when I'm back at the office.

> problem, tracking hardware problems using software symptoms constitutes
> undesirable pain and so it wouldn't hurt to give that a spin.  I remember
> seing your earlier e-mails about running with WITNESS increasing the
> chances of pain -- this could be a bug in WITNESS as you suggest, or it
> could be that WITNESS increases the opportunities for a variety of locking
> related races by increasing the cost of lock/unlock operations.

True. And I have already reconsidered my suggestion, since the removal
of WITNESS did not result in a stable system. Instead I just 
encountered tight lockups. The system was up a bit longer, though.

Regardless of the diagnostics to be done tomorrow, I will inspect
the latest crash, in which I was again lucky to get a crash-dump.
I will file a PR with my findings and mail the number to the -current
list. It was again inside of WITNESS code, this time a failed assertion.

Cheers,
 Daniel
-- 
IRCnet: Mr-Spock         - ceterum censeo Microsoftinem esse delendam -  
 Daniel Lang * dl_at_leo.org * +49 89 289 18532 * http://www.leo.org/~dl/
Received on Wed Jul 07 2004 - 15:41:17 UTC

This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:38:00 UTC