[PATCH] Re: IMAP: improve quickchanged() performance

[Nicolas Sebrecht]

On Mon, Apr 11, 2011 at 06:33:11PM +0200, Sebastian Spaeth wrote:
> 
> For each folder we were making a second IMAP request asking for the
> latest UID and compared that with the highest UID in our
> statusfolder. This catched the case that 1 mail has been deleted by
> someone else and another one has arrived since we checked, so that the
> total number of mails appears to not have changed.
> 
> I wonder if we want to capture this case in the quickchanged() case and
> am throwing this patch in for discussion by removing the check. It
> improves my performance from 8 to about 7.5 seconds per check (with lots
> of variation) and we would benefit even more in the IMAP<->IMAP case as
> we do one additional IMAP lookup per folder on each side then.
> 
> The downside is that we don't catch mails in the above scenario (someone
> deleted a mail remotely and a new one arrived)

Can't we try to fetch a deleted UID, then? How do we handle such case?

What's going on the next sync? Do we detect both changes and propagate
them locally?

-- 
Nicolas Sebrecht