[Dovecot] 1.2.9 imap crash with backtrace

[David Halik]

Same here. I laughed because our help desk started sending us the exact 
same complaints and then today I got a little bit of a red nose when a 
director's mail "disappeared" in a meeting. ;) Whoops.

It looks like users who end up with the off by 1 uid list rebuild and 
crash experience and empty inbox until the list is rebuilt and 
refreshed. I saw one user who experience the crash and then spewed about 
15K lines of "Duplicate message, uid -> uid". Since that takes awhile 
they probably couldn't see anything in the meantime.

Anyway, since we're hearing the complaints I went and remounted our IMAP 
servers with the "noac" NFS option today. So far it seems to have swept 
the problem under the rug, but our NFS server's Ops went from an average 
of 3-5K to 10K-20K, and the cpu went from 10% to 50% of constant load... 
so this is *definitely* only a temp fix. Hopefully Timo will have time 
to analyze the problem once his move is all finished.

-Dave

> I hope your move is going well, and you get settled in and your internet
> hooked up soon. It's got to be a rough process!
>
> Just for the record, we continue to see this crash fairly frequently
> with a small subset of our users, enough so that they have started to
> complain to the helpdesk staff about their mail 'disappearing and then
> reappearing.' One user in particular has a mail client left open from
> three hosts and has hit it 23 times in the last week, and 10 times
> today.
>
> If there's any more information I can collect or anything I can do to
> help get this resolved, please let me know!
>
> -Brad
>