Webmail applications that are kind to the IMAP server?

[Gary Mills]

On Mon, Sep 02, 2002 at 01:55:57PM -0400, Cyrus Daboo wrote:
> 
> The main areas that need to be looked at for performance in this case are:

Thanks for your response.  Thanks also to the others who responded.

> 1) The initial tcp connection between the webserver and imapserver. This 
> can easily be optimised in a closed environment, with the two servers 
> either on the same or different machines,
> 
> 2) The authentication process. This will likely depend on the 
> authentication method being used, but it really shouldn't be a major 
> performance issue.
> 
> 3) The mailbox 'open' (SELECT/SORT/FETCH etc). This is likely to be the big 
> performance hit. This will be very dependent on the IMAP server. For 
> example, the UW server has to reparse the entire mailbox for each SELECT, 
> thus performance gets noticeably worse the larger the mailbox is. The CMU 
> server caches message data, so SELECT is nearly independent of mailbox 
> size. If the user has set their webmail to sort by anything other than 
> message number, then a SORT command will be used. Both CMU and UW will have 
> to do the sort each time - they don't make any attempt to cache sort order.

Yes, that sounds right to me.  I've asked the person who installed IMP to
check on the default sort order.  That could well be the cause of the
high system load in our tests.

-- 
-Gary Mills-    -Unix Support-    -U of M Academic Computing and Networking-