[Dovecot] Index corruption causes child process to die

[Hr. Daniel Mikkelsen]

Timo Sirainen wrote:
> On Sun, 2006-11-12 at 16:02 +0200, Timo Sirainen wrote:
>> On Sun, 2006-11-12 at 15:52 +0200, Timo Sirainen wrote:
>>> On Wed, 2006-11-08 at 20:46 +0100, Luigi Rosa wrote:
>>>> Timo Sirainen said the following On 7/11/2006 22:39:
>>>>
>>>>> Oh, right, the patch.
>>>> It happened again ad was more serious.
>>>>
>>>> {two mail arrived from two different mailing lists, Thunderbirds moves 
>>>> them in their mailbox but...}
>>>>
>>>> Nov  8 20:36:44 mail dovecot: IMAP(lrosa): Fixed index file 
>>>> /var/spool/mail2/lrosa/.Postfix/dovecot.index: 
>>>> first_recent_uid_lowwater 10272 -> 10271
>>>> Nov  8 20:36:44 mail dovecot: IMAP(lrosa): Corrupted index file 
>>>> /var/spool/mail2/lrosa/.Postfix/dovecot.index: Duplicate header 
>>>> extension keywords
>>>> Nov  8 20:36:44 mail dovecot: child 12176 (imap) killed with signal 11
>> ..
>>> I tried reproducing this for a while with Thunderbird, but couldn't get
>>> these kind of errors.
>> No, forget it. I was finally able to reproduce this myself after setting
>> maildir_copy_with_hardlinks=yes. :) Now lets try to fix it..
> 
> Annoying. I tried to debug this for two hours, and it happened maybe 5
> times, but after I had added enough debugging code it stopped doing it
> completely (even without the debugging code).
> 
> I guess I'll have to write some test program which tries to emulate
> Thunderbird and make this crash happen more easily.
> 
> I did anyway see that the index file gets about 13 of these keyword
> extensions in it. Originally I thought there'd be just one extra, but
> this is weird..

FWIW: I've set "maildir_copy_with_hardlinks = no" as a workaround here,
and there's no discernable effect on performance.

The only effect I've been able to notice is that the index corruption
problem goes away. 

Perhaps just write this up as a known bug for 1.0 and explain the workaround? 

-- 
Daniel Mikkelsen
Copyleft Software AS