[Mailman-Users] duplicate messages

[Brad Barnett]

On 27 Apr 2003 16:53:22 -0400
Jon Carnes <jonc at nc.rr.com> wrote:

> > > > > > >Hey all,
> > > > > > >
> > > > > > >I've had a very bizarre situation occur with Mailman just
> > > > > > >last week. After one post to the list, Mailman started
> > > > > > >generating duplicate after duplicate of this same message. 
> > > > > > >It was caught in the process of sending the fourth message
> > > > > > >out.
> > > > > > >
> > > > > > >The list.mbox file shows 4 identical messages, even if using
> > > > > > >diff to check them against each other.  They all have the
> > > > > > >same message ID, the same send time, etc.  Each of these
> > > > > > >messages was sent to the over 10k users on this list, and I
> > > > > > >still don't know why.
> > > > > >
> > > > > > What version of Mailman are you using?
> > > > >
> > > > >
> > > > >2.0.13, on Redhat 8.0.
> > > > > >
> 
> I've only seen this kind of behavior in Mailman 2.0.13 when the server
> ran out of resources (or was restarted) in the middle of a delivery.
> 
> I suggest you look at your system resources - in particular your RAM and
> your disk space.  I have a feeling that you ran out of RAM while trying
> to process mail going out to your list.
> 

I can't see it being a ram issue.  This box has 256M of ram and 500M of
swap.  It (generally) does not put a heavy load on those resources.  Right
now it has 84M of ram free, after being up for a week, with almost no swap
used.  

My take on this is that the box hasn't even used all of its resources,
otherwise it would have ram full with cached libs and what not.  I also
just checked the boot.log on this box, and it was rebooted (for some odd
reason) just before the message was sent out.  This box has been using
Mailman for over a year with no issues, and was fresh (read, ram clean)
just before this batch was sent out.  

I don't think it was a ram issue.. and hard drive space seems fine.

Any other ideas or possibilities?    



> You'll see several instances in the archives where we have tracked this
> type of behavior down to a system resource problem.
> 
> Earlier versions of Mailman (like version 2.0.11) did have problems with
> malformed headers, which would cause this type of behavior, but 2.0.13
> has been very good about handling anything thrown at it.
> 
> BTW: when you get 4 identical messages where even the MSG-ID's are
> identical, then you know it's the same message being delivered multiple
> times.
> 
> Take care and good luck - Jon Carnes