Anders Lund wrote:
Could you try to see if switching to flock would make any difference? Just remember to make sure your MTA/LDA uses at least dotlocking if you cannot switch it to use flock.
Only for "lock_method", or the other two lock methods as well?
For mbox_read_locks and mbox_write_locks since your error messages look to me as some sort of problem with mbox file locking.
But.. I was able to reproduce "file mail-index-transaction.c: line 831 (mail_index_update_ext)" assertion couple times, I made backtrace of crash and sent it to Timo. This is still very hard to reproduce ..
I'm not sure I understand. Why would I gain a lot from using Dovecot LDA? Typically users could use Procmail for filtering, and deliver to their different mboxes. I might be interested in looking at Dovecot LDA because of SIEVE, but can't see how using it will give me any big advantages.
Dovecot LDA is designed to work with Dovecot so it integrates fully with your IMAP and POP3 facility, this simplifies things a lot on any larger scale sites.
Dovecot LDA adds extra headers to every message stored in mbox on initial delivery, otherways those headers are added by IMAP or POP3 process which requires rewriting parts of mbox file causing unwanted fsynced writes.
Dovecot LDA also updates indexes on message delivery time, with mbox this is very beneficial since mbox file offsets are stored into indexes so mbox file does not need to be parsed by IMAP or POP3 process. Dovecot is altough quite clever to avoid unneeded mbox parsing even without Dovecot LDA if you have "mbox_dirty_syncs" or "mbox_very_dirty_syncs" set, but I still prefer indexing on mail delivery time.
OK. I'll add "mail_drop_priv_before_exec" and see if I get any core files.
You also need to configure your Debian to allow crashing software to create core dumps.
Edit "/etc/security/limits.conf" and uncomment line:
soft core 2000
Then check that "/etc/profile" does not have "ulimit -c 0", comment it away if it is there.
Do a relogin and type "ulimit -c", if you see "2000" then your system allowing core dumps.
-- Tomi Hakala