KDE 4.11 showstopper: KMix lockup for 20 seconds, and a concept for fixing it

[Christian Esken]

Hello,

in KDE4.10 KMix officially got MPRIS2 support. All looked fine in the 
beginning, but soon there were complaints about lockups with Clementine 
or other Media players, especially during logging in. Several solutions 
failed. So I tried to draft a new solution - see the attachment in 
https://bugs.kde.org/show_bug.cgi?id=317926 . If somebody could comment 
on that it would be highly appreciated.

Impact: I myself am not directly affected. But for those who are 
affected the problem is highly annoying - nobody wants to have a login 
delay of 20 seconds and then also a only half working Mixer or Media 
player. This is very close to being a showstopper: extremely annoying, 
and that can be the first impression on KDE you get.

Here is some background information on what is happening:
MPRIS2 is using DBUS. I finally I got the notion that doing DBUS 
requests is evil - at least ANY synchronous DBUS communication. I am 
pretty sure I am not the first with these problems, so if anybody has 
working code that shows how to do it I would be glad. Or review my 
concept code.


  Christian

Bug report: https://bugs.kde.org/show_bug.cgi?id=317926