Panic: file mail-index-util.c: line 37 (mail_index_uint32_to_offset): assertion failed: (offset < 0x40000000)

[Stefan Neben]

Hi,

> Unfortunately dovecot has an in-built limit of
> 2GB for the index cache file

okay. I assumed there is a limit but not that low, thought about 4GB
because of this:

https://www.dovecot.org/list/dovecot/2015-September/101863.html

And the strange thing is, i had this problem yesterday twice. The
first time the index cache was 1.2GB and the second time it was 1.1GB.
Is there a second factor, which could limit this?

> Your only solution is to move some of the mails to some other folder.

Yes, this was my fallback solution, but this means a lot of work to
adapt the 3rd party tooling around it :-(

2018-01-11 12:33 GMT+01:00 Aki Tuomi <aki.tuomi at dovecot.fi>:
>
>
> On 10.01.2018 22:00, Stefan Neben wrote:
>> Hello,
>>
>> i have a problem with a very huge mail account.
>>
>> The INBOX of this account has ~1.1 - ~1.7 million mails inside. And
>> from time to time the index cache make problems and i got the
>> following in the logs:
>>
>> --- Snip ---
>> Jan 10 20:43:04 XXXXX dovecot: imap(XXXXX): Panic: file
>> mail-index-util.c: line 37 (mail_index_uint32_to_offset): assertion
>> failed: (offset < 0x40000000)
>> --- Snap ---
>>
>> I skip the raw backtrace to keep the post "small", but can hand it in
>> later if needed. Got this for UID FETCH, UID SEARCH, UID SORT, ...
>>
>> The size of the file dovecot.index.cache of INBOX was in the last seen
>> problem situations between 1.1GB to 2.3GB.
>>
>> To solve the problem the last times was to reduce the amount of mails
>> to under 1.7 million (seems to be the limit to trigger the problem),
>> delete the index cache and let him rebuild with a controled request.
>> But this is a odd situation (because it confused 3rd party tooling,
>> which access this mailbox) and i cannot find any helpful informations
>> to solve this problem.
>>
>> Sharding it into several folders to keep the amount of mails in INBOX
>> small is not an option currently.
>>
>> If further informations are needed, just let me know. Thanks for any help!
>>
>>
>> Kind regards
>> Stefan
> Hi!
>
> Unfortunately dovecot has an in-built limit of 2GB for the index cache
> file. Your only solution is to move some of the mails to some other folder.
>
> Aki