Sorry, i forgot to mention, that the storage format is mdbox and the version is 2.2.27-3~bpo8+1 from jessie backports.
Kind regards Stefan 2018-01-10 21:00 GMT+01:00 Stefan Neben <stefan.ne...@gmail.com>: > 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