[Kolab-devel] Kontact Performance, once again...

[ITSEF Admin]

Hi all,

I'm not 100% sure whether this should go to the users list, but responses 
there have been so few the last few times that I went for devel. Also, I 
think this really needs the eyeballs of someone with insight in 
Kolab/Kontact. :-/

I am *still* struggling with the performance of Kontact. I know there are 
several issues in the bugtracker, but I can't quite place what I'm seeing in 
any of them. One I found that might be related is 
https://intevation.de/roundup/kolab/issue1390

The original problem we had was using Kontact together with NFS home 
directories - to my great surprise, this seems to be an extremely unusal 
setup, given the responses on kolab-user. In the original configuration, 
Kontact would become very unresponsive as soon as a sync with the server 
started. After some investigation, our first conclusion was that the poor 
setup of our file server was part of the equation.

Since then, I have upgraded that server, so the home directories are served 
from a RAID10 array. Some simple tests with large files indicate that this 
array can easily saturate the 100Mb network connection our workstations 
currently have. I have since moved ~/.kde/share/config and 
~/.kde/share/apps/kmail/dimap back onto the NFS share again (we had them on 
the local drives as workaround - yes, *both* needed to be local to make 
Kontact's performance bearable) for my own account to run some tests. And 
again, when Kontact starts to sync, it becomes very sluggish as long as the 
sync runs. Any scrolling becomes jumpy, even typing can be delayed. Switching 
to a new folder becomes downright painful - and if any other network activity 
starts (e.g. copy some large files from local drive to NFS share), Kontact 
basically freezes.

When I monitor the network connection and the RAID array during the sync, I 
can see that neither is maxed out during the sync. The client itself (proko2 
after 2.1.4, currently revision 591884) runs on a P4/3.0GHz under SuSE 10.0. 
CPU load isn't very high during the sync. I currently have one split 
IMAP/DIMAP account (~230MB, ~70 folders) and two "pure" DIMAP accounts 
(~100MB/32 folders and ~170MB/120 folders) in Kontact.

I admit, I'm still not 100% convinced that Kontact itself *is* the culprit, 
but to investigate further, I'm certain I need input from folks with more 
knowledge of what Kontact is actually doing that puts so much load on the NFS 
system. I already had a look at strace and I can see many write actions 
(kmailrc/kdeglobals) during a sync - plus the dimap folders themselves, of 
course.

Any insight is welcome - and if any more testing on my part is needed, just 
let me know.

Cheerio,

Thomas