On Tue 2016-08-09 10:02:23 -0400, Matthias Beyer wrote:

> I wonder how notmuch tracks mails. Lets assume that we have a big
> Maildir tree - mails move around all the time - how does notmuch
> (re)find them? Is there a unique way to identify an email? As far as I
> know isn't the message id one of them, right?

notmuch uses message-id to identify individual mails.   this is a nice
simplification, but it leaves open some potentially problematic
situations that we have still never resolved (e.g. matching message-ids
on distinct mail, whether via malice or incompetence).

notmuch has maildir scanning code that is clever about tracking which
parts of various subtrees have changed recently and avoids having to
re-scan them if they haven't changed (this does require some cooperation
From the filesystem -- if you have an absolutely terrible filesystem, i
don't know how notmuch would handle the situation).

        --dkg