[kde-linux] Renicing KDE service daemons

[David Baron]

On Tuesday 10 February 2009 02:10:02 kde-linux-request at kde.org wrote:
> > Nepomuk has one, akonadi spawns several children for KABC resources, all
> > taking memory and CPU whether or not any client is using them. KDE4.2,
> > with all its improvements, seems to slow to a crawl. KMail is a big
> > victim/offender.
>
> Not sure how KMail is related to the other two since it is not yet using
> these services.

The latest and greatest Kmail is very problematic, not related to these 
services but may be effected by them. Crashes often on moving and deleting 
files, the problem is thread-related.
> Anyway, the service usually don't do anything on their own, just waiting
> for applications requesting their service.
> Depending on the system setup and kernel capabilities they might use some
> timer based file change monitoring, but on most systems they won't.
>
> So most of the time they will be sleeping.
>
At least for a long-enough period maybe for syncronization, these thingies are 
taking several percent each of CPU time. I believe that many posted compaints 
about overall slowness of reponse in kde4.2 are due to this!

> > I want this stuff to run niced. And seems to work on fully named
> > processes but not for regular expression names like akonadi.*
> >
> > How might one set up niceness in KDE's configs themselves?
>
> Since most services are either started through D-Bus activation or through
> the launcher service, their commands are usually specified in some kind of
> description file, e.g. .desktop or .service files.
>
> One could check if it is possible to extend the respective execution
> command with a nice command.
>
> However, since they get active as part of another processes service
> request, renicing them could potentially lead to problems, e.g. an
> application not getting a result because the service does not get run when
> the application is running in parallel with a better priority.
Since this is dbus-mediated, it should be possible to solve this problem if it 
does indeed exist. I have reniced this stuff manually and using "and" with no 
ill-effects but few things actually are active clients of these processes.
> Dispite running two KDE sessions in parallel, I don't see any of those
> services pop up in top other than an occasional 1% CPU of kded or kded4
Are you running akonadiserver? As I said, I see several %/each.
> Would be interesting to know which services take any noticable amount of
> processing power on your system while being idle.
OK, I'm am running on a PIII/600mhz clunker, but still ....