Graphical Glitches after Qt/KDE upgrade

caesius

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Just had a mass upgrade of most ports, including KDE4 and Qt. Now I've got some major problems with almost every Qt application. Sometimes they work fine, but after a while I will inevitably see a glitch like this.

Here is the output of starting a Qt application (Dolphin): http://pastebin.com/EqUze85f

The pertinent points seem to be:
Code:
dolphin(2252)/KSharedDataCache: Unable to perform initial setup, this system probably does not really
 support process-shared pthreads or semaphores, even though it claims otherwise.
dolphin(2252)/KSharedDataCache: Unable to unmap shared memory segment 0x2db29000
Thereafter whenever I move the mouse in the window's focus I see the stream below ad infinitum.
Code:
X Error: BadPixmap (invalid Pixmap parameter) 4
  Major opcode: 56 (X_ChangeGC)
  Resource id:  0x0
X Error: BadDrawable (invalid Pixmap or Window parameter) 9
  Major opcode: 62 (X_CopyArea)
  Resource id:  0x0

[... and so on ...]
I've also seen this error when starting Kate,
Code:
QDBusConnection: session D-Bus connection created before QCoreApplication. Application may misbehave.
I'm banging my head against the wall now; this does not happen with any GTK applications. Could my graphics card be kaput? The only other piece of information is the glitching usually starts happening after maximizing a window, and can sometimes be stopped by making it smaller.

Here is my system, please ask if you need more info, cheers.
Code:
FreeBSD blackbox.hansons 8.2-STABLE FreeBSD 8.2-STABLE #0: Sat Mar 26 19:15:18 NZDT 2011     
benjamin@blackbox.hansons:/usr/obj/usr/src/sys/BLACKBOX  i386
 
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caesius

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EDIT: I was wrong; after a period of use, the problem even shows itself under Fluxbox.

Possibly useful piece of information: I have started Fluxbox; I am not seeing the same glitching when running Qt applications now. I think it's safe to say I only see this issue when running KDE.

KDE is doing something strange?
 
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caesius

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I was hoping you would reply :)

Code:
shminfo:
        shmmax:     33554432    (max shared memory segment size)
        shmmin:            1    (min shared memory segment size)
        shmmni:          192    (max number of shared memory identifiers)
        shmseg:          128    (max shared memory segments per process)
        shmall:         8192    (max amount of shared memory in pages)
 

avilla@

Well-Known Member
Developer

Reaction score: 58
Messages: 258

:)

As per /usr/ports/x11-toolkits/qt4-gui/pkg-message:

Code:
Qt paint engine makes common use of shared memory. To avoid MIT-SHM
errors (i.e., blank windows), you probably need to tune shared memory
limits in loader.conf(5). The following should be safe values for the
KDE Plasma Desktop:

kern.ipc.shmmni=1024
kern.ipc.shmseg=1024
Additionally, you need to raise your shmall as you're on FreeBSD 8. 32768 should be a safe value (we'll add that to pkg-message soon).
 
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caesius

Well-Known Member

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Messages: 280

Thanks avilla,

Yep I had seen that message, and had those two in my /boot/loader.conf, but the problem persisted (I later commented them out, that's why they don't show in my ipcs -M output above).

However changing shmall to 32768 looks like it has done the trick though, definitely a good idea to add that to pkg-message for us still using FreeBSD 8. ;)

Cheers!
 

avilla@

Well-Known Member
Developer

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Messages: 258

caesius said:
However changing shmall to 32768 looks like it has done the trick though, definitely a good idea to add that to pkg-message for us still using FreeBSD 8. ;)
We were just waiting for a sane value to be tested, and this one now looks fine.
 

rdlfree

Member


Messages: 26

Would you set these values in /etc/sysctl or would you set the same values in both (i.e. sysctl and loader.conf)?
 

SR_Ind

Active Member

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Messages: 127

FWIW...I used to see this problem till last year or so, only when I used to select Cleanlooks theme.

Point to note is that I'm not a KDE user. I stick with Plastic theme that comes with stock installation or sometime use QtCurve theme.
 
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