email notification regression between 2.2 and 2.3

[Thomas Capricelli]

Hi,


Hello.

For the last year, each time i've tried updating dovecot from 2.2.x to 
2.3.x, I had to rollback because of the following problem:

Users don't "see" new emails arriving in subdirs.

To be specific
* we mostly use/tested thunderbird client
* we use maildrop for delivery
* this is using imap, not pop3
* when a new email arrives, thunderbird renders the dir name in blue and 
appends a "(1)" (or more..). That's what we call 'see'
* this happens only on 'subdirs', not the main directory.
* the server is a typical linux amd64, using the gentoo distribution


More testing shows that
* if we switch delivery to dovecot-lda, it works ok. But we can't commit 
that change, or at least not now/easily. Our users heavily use .mailfilter
* if the user is currently viewing the subdir, then email notification 
is working
* better : if the user went on the subdir and then in another dir, it 
keeps on working. It seems we need to 'open' it at least once for 
notification to work
* "maildir_very_dirty_syncs = no" doesn't help (we had =yes)
* "mailbox_list_index = no" doesn't help
* i can confirm inotify was detected/used in autoconf when installed 
(anyway it works well with 2.2)


I'm always on freenode (orzel). I'll be in #dovecot the next days at least.


greetings,
-- 
Thomas Capricelli