Quoting Timo Sirainen <tss@iki.fi>:
On 8.11.2012, at 0.08, Michael M Slusarz wrote:
I'm not sure changing the defaults is a good idea. But if someone
does want to use a particular dovecot server as the backend for
activesync clients, for example, it would probably make sense to
allow these values to be tweaked via the config files. (I can see
an organization having a "normal" IMAP server and a "activesync"
IMAP server that differ in these details, and also in things like
IDLE timeouts).Well .. I hate adding more settings. :) There are way too many
already. Ideally Dovecot would automatically do the right thing
anyway. Just like it already caches only those things that are
needed. It could also increase these values when QRESYNC is used, or
even better to actually have the separate expunge log that I
mentioned.
Thinking about this more, this can really all be handled by proper MUA
design. In short, it is never a good idea to send a '1:*' UID range
to a VANISHED CHANGEDSINCE FETCH.
It remains a reasonable MUA design decision to not send the actual
cached UID list to the FETCH command: if this cached UID list is
thousands of messages long, obtaining this list, (optionally) sequence
set compressing, and sending via the command may take more
time/resources than it saves. But a MUA should, at a minimum, keep
track of the minimum UID it is aware of in order to limit the possible
response. This is a trivial amount of extra overhead and would
prevent a large number of spurious VANISHED UIDs to need to be
traversed.
michael