[Bug 248466] New: IMAP move operation slower the more messages are selected

[David Jander]

https://bugs.kde.org/show_bug.cgi?id=248466

           Summary: IMAP move operation slower the more messages are
                    selected
           Product: kmail
           Version: unspecified
          Platform: Ubuntu Packages
        OS/Version: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: NOR
         Component: IMAP
        AssignedTo: kdepim-bugs at kde.org
        ReportedBy: djander at gmail.com


Version:           unspecified (using KDE 4.3.2) 
OS:                Linux

Moving several messages from one imap folder to another is already very slow in
kmail, but the worst thing is, it gets proportionally slower the more messages
are selected. It seems as if at first all individual move operations are queued
in a list at once (that takes some time), and then this list is processed one
message at a time, and somehow it takes longer to select the next operation out
of this list, the longer this list is. Moving a few thousand messages on a
local imap server (1Gb connection) can take hours!!

Reproducible: Didn't try

Steps to Reproduce:
Chose a IMAP folder with many messages (for example from a mailing list).
Create a second folder.
Select 100 messages from the first folder and move them to the second folder.
Time the operation.
Select 1000 messages from the first folder and move them to the second folder.
Time the operation.

Actual Results:  
The second operation (1000 messages) takes much more than 10 times the time of
the first operation (100 messages).

Expected Results:  
The second operation (1000 messages) should take approximately 10 times the
time to complete than the first move operation (100 messages).

1.- When clicking on the arrow button on the status bar to show the list of
pending operations while moving a few thousand messages, kmail freezes a very
long time to show the list (which is very long). It seems to me that this code
is not scaleable and the whole job processing should be re-designed.

2.- IMAP supports copying multiple messages in one command. It seems utterly
inefficient that kmail apparently does not use this feature.

3.- I remember doing the same sort of operations in kde-3.5 in the past and it
didn't even be nearly as slow, although my computer was much slower back then.

-- 
Configure bugmail: https://bugs.kde.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.