Hello,

For a very long time, I've been finding kmail take a *very* long time to synchronize my IMAP account. It takes about a half-hour to retrieve new messages. Also when I click a listed message, I see the text "Retrieving Folder Contents" for about the same time before the actual content is shown. At this point, kmail is pretty much unusable for me.

I tried to debug this a bit today. Following the Debug_IMAP instructions, I used KIMAP_LOGFILE to dump the IMAP communication log. I see the following stream of messages, with the UID incrementing by a 1000 each time.

Code: Select all

C: A008188 UID SEARCH UID 16360001:16362000
S: * SEARCH
S: A008188 OK SEARCH completed.


At the beginning, I see the following SELECT command:

Code: Select all

C: A000005 SELECT "INBOX"
S: * 91710 EXISTS
S: * 0 RECENT
S: * FLAGS ( \Seen \Answered \Flagged \Deleted \Draft $MDNSent )
S: * OK Permanent flags [ PERMANENTFLAGS ( \Seen \Answered \Flagged \Deleted \Draft $MDNSent )  ]
S: * OK Is the first unseen message [ UNSEEN 42210  ]
S: * OK UIDVALIDITY value [ UIDVALIDITY 209099  ]
S: * OK The next unique identifier value [ UIDNEXT 22490418  ]
S: A000005 OK SELECT completed. [ READ-WRITE  ]


This is my primary work email that I've had for many years now. I'm subscribed to several mailing list and have notifications for random tasks (those can grow quite large, I usually delete them right away using a filter). Thus the number of unique ID's during the entire existence is not too surprising, although 22M does seem quite large.

From the KIMAP_LOGFILE, I am inferring that every time I start kmail, akonadi goes through every single one of them to see which ones are valid. Since there are 22M UID's, this process takes a while.

Once this search phase completes, akonadi starts doing a bunch of "UID FETCH" for the 900k emails that actually exist. At this point, the progress bar at the bottom of kmail starts to increment from 0%. This part completes relatively quickly.

But once the fetching finishes, the searching for valid UIDs that locks everything up starts again and makes kmail unresponsive.

Does this seem like the right diagnosis of my problem? If so, is there anything I can do to improve my situation? Is there some way to get the mail server to for a reset the UID count?

More information about what I use.
IMAP server: Microsoft Exchange Server 2010 IMAP4
Kmail: 5.12.1
Akonadi: 19.08.2
KDE Frameworks 5.63.0
OS: Gentoo Linux

--
Karol Krizka