Dovecot 2.2.16: disappearing messages, mismatched summaries, duplicated messages, excessive full re-downloads

[Timo Sirainen]

On 16 Jun 2015, at 03:50, David Gessel <gessel at blackrosetech.com> wrote:
> 
>> Alessio Cecchi skrev den 2015-06-01 15:29:
>>> Il 20/05/2015 10:44, David Gessel ha scritto:
>>>> Is there a way to completely disable caching on dovecot?
>>> 
>>> Yes: mail_location = maildir:~/Maildir:INDEX=MEMORY
>> 
>> dont know if that really solve it, imho it just move the problem from disk cache to memory cache, it does not imho disable it
> 
> 
> It seemed to do the trick.  Behavior finally seems normal.  The best evidence:  At 10:00:00-ish I made the change in the config file and at 10:02:29 I restarted the server.
> 
> It is now after 17:14 in Oakland and the logs are quiet.
> 
> 09:00:06 host newsyslog[55292]: logfile turned over due to size>1000K
> 09:00:08 imap(user1): Warning: Maildir /mail/dom1.com/user1/: Expunged message reappeared, giving a new UID (old uid=3558585, file=1434383291.M430136P55004.host,S=2380,W=2423:2,)
> 09:00:08 imap(user1): Warning: Maildir /mail/dom1.com/user1/: Expunged message reappeared, giving a new UID (old uid=3558586, file=1434383253.M121801P54997.host,S=27419,W=28395:2,)
..
> The last log file was turned over when it got greater than 1000K.  It covered 1312 minutes and 3726 "expunged Message" warnings or one every 21 seconds.  There hasn't been a single one in the 7+ hours since I moved the index to MEMORY.
> 
> Whatever is confusing the index state on disk, it is not happening in RAM. 

Well, it's also possible that the confusion is still happening, but Dovecot just doesn't notice it. If it is, IMAP clients may randomly not see all messages or may otherwise have strange behavior.