Especially soon after triggering a mail retrieval from my POP3 accounts I have it that KMail is unresponsive.

Reproducible: Sometimes

Steps to Reproduce:
1. Have an POP3 account with LKML and some other high volume lists.
2. Let it pile up mails over night.
3. Retrieve messages the next morning
Actual Results:  
Sometimes KMail / Akonadi server doesn´t respond in a timely manner. Examples:

1) I click on a message in the message list. In the message reader pane KMail shows that it retrieves the message for minutes.

2) I click on a folder, like inbox, with about some thousand mails and it just shows the spinning wheel before the folder name for minutes

Expected Results:  
On an ThinkPad T520 with Intel Sandybridge i5-2520M 2,5GHz, that the ThinkPad lets overtact itself to about 3/3.2 GHz for extended period of times hyperthreaded dual core CPU, 8 GB of RAM, and an 300 GB SATA 300 Intel SSD 320 I expect reactions to user input in KMail to be about instant at all times, except for maybe really large folders, where it may take some seconds.

During this behaviour I get stuff like the following in ~/.xsession-errors:


ItemRetrieverException :  Unable to retrieve item from resource: Did not receive a reply. Possible causes include: the remote application did not s
end a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken.
kmail2(13538)/libakonadi Akonadi::EntityTreeModelPrivate::fetchJobDone: Job error:  "Unable to fetch item from backend (collection 35) : Unable to 
retrieve item from resource: Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus securit
y policy blocked the reply, the reply timeout expired, or the network connection was broken." for collection: 35 


ItemRetrieverException :  Unable to retrieve item from resource: Did not receive a reply. Possible causes include: the remote application did not s
end a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken.
kmail2(13538)/libakonadi Akonadi::EntityTreeModelPrivate::fetchJobDone: Job error:  "Unable to fetch item from backend (collection 35) : Unable to 
retrieve item from resource: Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus securit
y policy blocked the reply, the reply timeout expired, or the network connection was broken." for collection: 35 


This morning I also have:

kmail2(13538)/libakonadi Akonadi::EntityTreeModelPrivate::monitoredItemChanged: Got a stale notification for an item which was already removed. 447
047 "1365845303.R253.merkaba" 

After some minutes now things have settled down and I am able to see the new mail again.

During this occurence often the system is not fully under load. It was using "only" about 2 of the 4 logical cores of the CPU. And it wasn´t using all of the availble SSD bandwidth / IOPS. Thus I suspect some issue with communiction between different components of Akonadi / KMail / Nepomuk.

While this doesn´t make the software completely unusable, I think its still more than Normal in severity. Well, you choose.

This may be related to:

[Bug 318234] New: KMail sometimes does not update source folder view on move or mark operations unless restarted

I use the following setup:

1) I had all mails in ~/Mail

2) I moved all recent mails from ~/Mail to a newly created BTRFS subvolume ~/.Mail so that I can snapshot it. I moved all the archived mails to ~/.Mail-Archiv, as these are mbox folders.

3) Then I let the migrator run so that it puts my account information into kmail2rc.

4) For each POP3 account I use I created an extra maildir agent pointing it at the maildir and then selecting "Synchronize All" in Akonadiconsole. Thus for my main account Lichtvoll I gave it ~/.Mail/Lichtvoll as maildir directory for example:

drwx------ 1 martin martin        18 Apr 11 08:33 Lichtvoll
drwx------ 1 martin martin      4106 Apr 11 17:28 .Lichtvoll.directory
-rw------- 1 martin martin   4312743 Apr 11 08:33 .Lichtvoll.index
-rw------- 1 martin martin     33909 Apr 11 08:33 .Lichtvoll.index.ids

For local mails I created:

drwx------ 1 martin martin        18 Jan  2 11:36 Lokal
drwxr-xr-x 1 martin martin       528 Apr 11 09:50 .Lokal.directory

and copied all the local mail folders into that.

5) I imported my filter rules back to this new setup, set inboxes for mail download to the right top level maildir directories and so on.


Size of setup:

martin@merkaba:~> find ~/.Mail | wc -l
431234
martin@merkaba:~> du -sh ~/.Mail
6,5G    /home/martin/.Mail


The KDEPIM-2 packages are from Debian developers, but they are not publically available in official Debian repositories. I test them for for them.

martin@merkaba:~> apt-show-versions | egrep "(kdepim|korganizer|kmail|knode|kaddressbook|zanshin|akonadi|nepomuk|strigi|virtuoso|soprano|libqt)"   akonadi-backend-mysql/experimental uptodate 1.9.1-2
akonadi-backend-postgresql/experimental uptodate 1.9.1-2
akonadi-backend-sqlite/experimental uptodate 1.9.1-2
akonadi-server/experimental uptodate 1.9.1-2
akonadiconsole 4:4.10.2-0r4 newer than version in archive
kaddressbook 4:4.10.2-0r4 newer than version in archive
kaddressbook-mobile 4:4.10.2-0r4 installed: No available version in archive
kdegraphics-strigi-analyzer/sid uptodate 4:4.8.4-1
kdepim 4:4.10.2-0r4 newer than version in archive
kdepim-dbg 4:4.10.2-0r4 newer than version in archive
kdepim-kresources 4:4.10.2-0r4 newer than version in archive
kdepim-mobileui-data 4:4.10.2-0r4 installed: No available version in archive
kdepim-runtime/experimental uptodate 4:4.10.2-1
kdepim-strigi-plugins 4:4.10.2-0r4 newer than version in archive
kdepimlibs-dbg/experimental uptodate 4:4.10.2-1
kdepimlibs-kio-plugins/experimental uptodate 4:4.10.2-1
kdesdk-strigi-plugins/sid uptodate 4:4.8.4+dfsg-1
kmail 4:4.10.2-0r4 newer than version in archive
kmail-mobile 4:4.10.2-0r4 installed: No available version in archive
knode 4:4.10.2-0r4 newer than version in archive
korganizer 4:4.10.2-0r4 newer than version in archive
korganizer-mobile 4:4.10.2-0r4 installed: No available version in archive
libakonadi-calendar4/experimental uptodate 4:4.10.2-1
libakonadi-contact4/experimental uptodate 4:4.10.2-1
libakonadi-kabc4/experimental uptodate 4:4.10.2-1
libakonadi-kcal4/experimental uptodate 4:4.10.2-1
libakonadi-kde4/experimental uptodate 4:4.10.2-1
libakonadi-kmime4/experimental uptodate 4:4.10.2-1
libakonadi-notes4/experimental uptodate 4:4.10.2-1
libakonadi-socialutils4/experimental uptodate 4:4.10.2-1
libakonadiprotocolinternals1/experimental uptodate 1.9.1-2
libkdepim4 4:4.10.2-0r4 newer than version in archive
libkdepimdbusinterfaces4 4:4.10.2-0r4 installed: No available version in archive
libkdepimmobileui4 4:4.10.2-0r4 installed: No available version in archive
libnepomuk4/experimental uptodate 4:4.10.2-2
libnepomukcore4/experimental uptodate 4:4.10.2-1
libnepomukquery4a/experimental uptodate 4:4.10.2-2
libnepomukutils4/experimental uptodate 4:4.10.2-2
libnepomukwidgets4/experimental uptodate 4:4.10.2-1
libqt4-dbg/sid uptodate 4:4.8.2+dfsg-11
libqt4-dbus/sid uptodate 4:4.8.2+dfsg-11
libqt4-declarative/sid uptodate 4:4.8.2+dfsg-11
libqt4-designer/sid uptodate 4:4.8.2+dfsg-11
libqt4-dev/sid uptodate 4:4.8.2+dfsg-11
libqt4-dev-bin/sid uptodate 4:4.8.2+dfsg-11
libqt4-help/sid uptodate 4:4.8.2+dfsg-11
libqt4-network/sid uptodate 4:4.8.2+dfsg-11
libqt4-opengl/sid uptodate 4:4.8.2+dfsg-11
libqt4-qt3support/sid uptodate 4:4.8.2+dfsg-11
libqt4-script/sid uptodate 4:4.8.2+dfsg-11
libqt4-scripttools/sid uptodate 4:4.8.2+dfsg-11
libqt4-sql/sid uptodate 4:4.8.2+dfsg-11
libqt4-sql-mysql/sid uptodate 4:4.8.2+dfsg-11
libqt4-sql-psql/sid uptodate 4:4.8.2+dfsg-11
libqt4-sql-sqlite/sid uptodate 4:4.8.2+dfsg-11
libqt4-svg/sid uptodate 4:4.8.2+dfsg-11
libqt4-test/sid uptodate 4:4.8.2+dfsg-11
libqt4-xml/sid uptodate 4:4.8.2+dfsg-11
libqt4-xmlpatterns/sid uptodate 4:4.8.2+dfsg-11
libqtassistantclient4/sid uptodate 4.6.3-4
libqtcore4/sid uptodate 4:4.8.2+dfsg-11
libqtdbus4/sid uptodate 4:4.8.2+dfsg-11
libqtglib-2.0-0/sid uptodate 0.10.2-2
libqtgstreamer-0.10-0/sid uptodate 0.10.2-2
libqtgstreamerui-0.10-0/sid uptodate 0.10.2-2
libqtgui4/sid uptodate 4:4.8.2+dfsg-11
libqtlocation1/sid uptodate 1.2.0-3
libqtruby4shared2/sid uptodate 4:4.8.4-1
libqtscript4-core/sid uptodate 0.2.0-1
libqtscript4-gui/sid uptodate 0.2.0-1
libqtscript4-network/sid uptodate 0.2.0-1
libqtscript4-sql/sid uptodate 0.2.0-1
libqtscript4-uitools/sid uptodate 0.2.0-1
libqtscript4-xml/sid uptodate 0.2.0-1
libqtwebkit-dev/sid uptodate 2.2.1-5
libqtwebkit4/sid uptodate 2.2.1-5
libqtwebkit4-dbg/sid uptodate 2.2.1-5
libqtxdg0/sid uptodate 0.4.1-2
libsmokeakonadi3/sid uptodate 4:4.8.4-1
libsmokenepomuk3/sid uptodate 4:4.8.4-1
libsmokesoprano3/sid uptodate 4:4.8.4-1
libsoprano-dev/experimental uptodate 2.9.0+dfsg1-1
libsoprano4/experimental uptodate 2.9.0+dfsg1-1
nepomuk-core-data/experimental uptodate 4:4.10.2-1
nepomuk-core-runtime/experimental uptodate 4:4.10.2-1
ruby-akonadi/sid uptodate 4:4.8.4-1
ruby-soprano/sid uptodate 4:4.8.4-1
soprano-daemon/experimental uptodate 2.9.0+dfsg1-1
virtuoso-minimal/experimental-snapshots uptodate 6.1.6+dfsg1-0r1
virtuoso-opensource-6.1-bin/experimental-snapshots uptodate 6.1.6+dfsg1-0r1
virtuoso-opensource-6.1-common/experimental-snapshots uptodate 6.1.6+dfsg1-0r1
zanshin/sid uptodate 0.2.1-1+b1