[imp] login slowness with large inboxes after upgrade from Horde 3.0.10+IMP 4.0.4 to Horde 3.3.8 + IMP 4.3.7

[Michael M Slusarz]

Quoting Jose Manuel Blanco <jmblanco at sciops.esa.int>:

> Regarding the IMAP server side suggestions, the thing is that my old  
> webmail (Horde 3.0.10+IMP 4.0.4) is connecting to the same IMAP  
> server, and it has no problems dealing with large inboxes -1 or 2  
> seconds max. for displaying inboxes with more than 40000 mails never  
> been cached-, so my question remains: has the imp code changed in a  
> way that would explain that behaviour? For example, when I click in  
> the Date tab to reorder my messages, my old webmail only reorders  
> the ones that are visible

No.  As previously described - this can NEVER happen with IMAP.  IMAP  
requires a full sort of ALL messages in the mailbox - not a mailbox  
slice.

> while the new one goes to the first (or last) page instead. This  
> suggests that the old one is only dealing with the ones that are  
> visible, but I can't be sure. The settings are the same in both  
> webmails as far as I can see.

What is probably happening is that somewhere between IMP 4.0 and IMP  
4.3 sorting got fixed.  So clicking on Date now correctly sorts by the  
date in the headers of the message vs. the IMAP sequence number (which  
is often a date sort, but not always).  Sorting by sequence numbers is  
extremely fast because it is the only operation that doesn't require  
sorting at all - you can just grab a message slice.  But sorting by  
sequence numbers is also not very useful since messages may appear to  
be in a random order.  That's the tradeoff.

michael

-- 
___________________________________
Michael Slusarz [slusarz at horde.org]