[imp] Slowness with big mailboxes

[Joseph Brennan]

--On Monday, October 1, 2001 09:55 -0400 Chuck Hagenbuch <chuck@horde.org> wrote:

> Quoting Joseph Brennan <brennan@columbia.edu>:
> 
>> I wonder if IMP should download the mailbox to local temp space, and
>> then read from the local copy.  IMP could store changes and connect to
>> the IMAP server every configurable N minutes to synch the changes, 
>> similar to PC clients' offline mode.  IMP would look faster to users.
> 
> Yar. If you can provide a working demo of that, I'd be interested in what kind 
> of load that puts on the server, how well it stays in sync, and how massive the 
> changes needed would be.


I honestly wish I had the time and PHP knowledge to work on it.  It could
be a fruitful line of attack. 

Actually on second thought it would still be bad for huge mailboxes.  The 
opening transaction would have to transfer the entire mailbox which would
take way longer than getting the header info.  It would probably be 
practical only for a case where the IMP server was limited to accessing
one IMAP server and does so as localhost or via a high bandwidth connection 
in the same machine room.  That case does seem to be common though.

What might work out would be an alternative "quick check new mail" option.
This would send imap commands to transfer just text parts of "new unseen" 
messages to local temp space, and when user says logout, send back the 
flag changes and an expunge command.  Tune it for efficiency.  Usefulness 
assumes some significant number of sessions take place because users just 
want to see if there's interesting new mail.  I suspect this is the case.

Joseph Brennan                           postmaster@columbia.edu
Academic Technologies Group, Academic Information Systems (AcIS)