About two months ago I installed Kubuntu 15.04. After a few weeks it become completely unusable: crashes, freezes – horrible.
Luckily Kubuntu 15.10 was available and I upgraded. Right from the start I had massive problems with graphics. I could solve most of them by using the newest driver for my NVidia card.

Still I have so many problems that I am not sure if I soon will decide that the newest Kubuntu is not usable – for me. But I still have hope.
Here is an incomplete (!) list, in no particular order:

1. Several times a day kwin_x11 crashes. (Luckily I know how to restart it, most of the time I am even able to do it.)

2. KRunner doesn’t know my $PATH. For this I already got a solution here in the forum (https://forum.kde.org/viewtopic.php?f=66&t=129227).

3. Parallel sessions, I used them a lot with KDE 3.5 on openSUSE, are not usable. When I change to a second session two processes of the now inactive user consume almost completely my two processor cores: kscreenlocker_greet and kwin_x11.
Maybe that’s why the login screen then is sometimes partially corrupted:
– In the displayed time and date some characters are missing leaving emtpy spaces.
– None of the avatar pictures has a caption, nor has the button.

4. Login screen, always, even with no parallel sessions: The dropdown button for choosing the keyboard layout left of the password input box has a width of less than one character. I can only see that there is something in there, but I can’t read it. This is a problem because I use different keyboard layouts.

5. Sometimes the taskbar, set to “Auto Hide”, pops up when I do something like opening a new Konqueror window with a shortcut.

6. Watching a video in VLC in fullscreen is occasionally not possible, showing a black screen instead. There are several levels of this effect.
a. No problem at all, fullscreen in VLC works fine.
b. The video shows in a non-fullscreen window but freezes (not black!) at a certain point if I enlarge the window. After a few tries or after some time a big window and even fullscreen is possible.
c. Same as b., but the attempt to fullscreen or even large window leads to black picture.
d. Interesting: Even a tiny VLC window only shows black, but I can watch the video in Dragon Player without problems.
e. Even Dragon Player begins to have the same problems as VLC.
Audio is never a problem. During one session, it never changes to a better working of these levels.
In none of these scenarios I have ever found any process consuming remarkable CPU percentage.

7. Session restore: KWrite and Konsole windows are not restored. (I think this is a long known bug.)

8. After login it takes up to 90 seconds until everything works, the taskbar being the last. In Kubuntu 15.04 it was just a few seconds.

9. Custom hotkeys: I have several hotkeys to start programs, e. g. Konqueror and Konsole, the same hotkeys in two user accounts, private and work. The hotkey for Konsole works in both accounts, the hotkey for Konqueror works in the work account but not in the private one. (Just as an anecdote: In Kubuntu 15.04 it was worse: Sometimes all hotkeys worked, sometimes some of them didn’t.)

Minor problems/bugs:

10. After login only the shadow of the taskbar is visible for a long time.

11. The taskbar is set to “Auto Hide”. After login it is visible.

12. Sometimes on KDE logout a dialog box pops up telling something like “kdeinit5 unextectedly terminated” and that sending an error report isn’t possible.

There is more but now I want to have this thing posted!

My hardware is more than four years old.

This topic can have at least two purposes:
1. I get help and will be able to work properly.
2. To show how many problems can occur in one Kubuntu 15.10 installation. That’s why I didn't start 12 different topics.

My impression of Kubuntu 5.4.2: should be called “5 beta”. Yes, I know this is subjective. Maybe this is just me, just bad luck, but nevertheless it is disappointing and frustrating.

qadeo wrote:1. Several times a day kwin_x11 crashes. (Luckily I know how to restart it, most of the time I am even able to do it.)

Segfault? kwin_x11 should autorestart.

qadeo wrote:3. Parallel sessions, I used them a lot with KDE 3.5 on openSUSE, are not usable. When I change to a second session two processes of the now inactive user consume almost completely my two processor cores: kscreenlocker_greet and kwin_x11.

Sounds like a driver bug, the driver on the other session is waiting for a retrace that's not gonna come up.
If you use the breeze decoration (aurorae themes will use OpenGL on QtQuick) you can mute kwin_x11 by suspending the compositor. The screenlocker greeter on QtQuick will be hard to stall - but you can (as a workaround) "kill -SIGSTOP" the offending processes on the other VT.
Maybe there's a way to work around that on the driver level (downforcing vertical sync)

qadeo wrote:6. Watching a video in VLC in fullscreen is occasionally not possible, showing a black screen instead. There are several levels of this effect.
...

Sounds like a driver bug as well.
Try on suspended compositing (SHIFT+Alt+F12) and paste the outputs of
- glxinfo
- qdbus org.kde.KWin /KWin supportInformation
and
- /var/log/Xorg.0.log
somewhere.

qadeo wrote:7. Session restore: KWrite and Konsole windows are not restored. (I think this is a long known bug.)

In Qt5, yes - unfortunately.

qadeo wrote:9. Custom hotkeys: I have several hotkeys to start programs, e. g. Konqueror and Konsole, the same hotkeys in two user accounts, private and work. The hotkey for Konsole works in both accounts, the hotkey for Konqueror works in the work account but not in the private one. (Just as an anecdote: In Kubuntu 15.04 it was worse: Sometimes all hotkeys worked, sometimes some of them didn’t.)

Keyboard layout (qwerty, qwertz, azerty, ...) and konqueror shortcut?
(See https://git.reviewboard.kde.org/r/125786/ )
Notice that esp. khotkeys was apparently unmaintained and severely broke on porting, see eg. https://bugs.kde.org/show_bug.cgi?id=343891
Situation should be better on 5.5

qadeo wrote:10. After login only the shadow of the taskbar is visible for a long time.

That falls into the "takes 90 seconds" issue categrory - QtQuick is slow as (well, every term I could enter here will be censored by the board)

qadeo wrote:11. The taskbar is set to “Auto Hide”. After login it is visible.

*Could* be covered by https://quickgit.kde.org/?p=kwin.git&a= ... e94ca04a51

qadeo wrote:My impression of Kubuntu 5.4.2: should be called “5 beta”. Yes, I know this is subjective. Maybe this is just me, just bad luck, but nevertheless it is disappointing and frustrating.

Please notice that this is not a KUbuntu board.

qadeo wrote:My impression of Kubuntu 5.4.2: should be called “5 beta”. Yes, I know this is subjective. Maybe this is just me, just bad luck, but nevertheless it is disappointing and frustrating.

Kubuntu feedback: http://www.kubuntu.org -> News: http://www.kubuntu.org/news/ -> Kubuntu 15.10: http://www.kubuntu.org/news/kubuntu-15-10/

I really don’t want to bother the wrong forum with my questions. I just recently started “getting involed” by giving feedback like this.

KDE always comes with a distribution.
Please help me to learn for the future:
How do I know whether it is a KDE or a Kubuntu or an Ubuntu problem?
Which of these problems belong to Kubuntu but not to KDE?

I just emphasized the Kubuntu version because I wanted to provide information about my system and I am really confused about the KDE version. I know that there is plasma, frameworks, and applications so I thought “Kubuntu 15.10” would be good enough to identify all of these parts. Sorry if I was wrong.

13. The “About KDE” of Konsole and KWrite don't show any version information (German version). There are four tabs, neither of them containing any number (I know there is in “About Konsole”). Apparently there are at least two different structures/layouts for the information in the “About” dialog boxes: Konqueror vs. Konsole and KWrite.

14. OK, I just learned that Konqueror is part of KDE Software Compilation 4. Still I am puzzled that “About KDE” in Konqueror shows “platform version 4.14.13”. Is there another group besides plasma, frameworks, and applications that is called “platform”? Sorry in advance if I am too ignorant of naming conventions and version numbers in KDE but until recently I mainly used it.


@luebking: Thanks for your efforts so far. It might take me some time to try your suggestions and provide the information. One thing I can say right away:
9. Custom hotkeys
The hotkey for keyboard layout switching works prefectly. It didn't in Kubuntu 15.04 tough – sometimes.
It’s the hotkey for the program “Konsole” that works only in one of my user accounts.

Notice that esp. khotkeys was apparently unmaintained and severely broke on porting, see eg. https://bugs.kde.org/show_bug.cgi?id=343891
Situation should be better on 5.5

To understand if I (still) belong to the target audience of KDE or to understand which KDE version I have to choose, and really not offence meant and definitely not against you:
Does this mean I can’t use KDE 5.0 through 5.4 if I want to use custom hotkeys?

For clarification: it's "upstreams" (KDE/Qt/gilbc/...) job to provide usable software, but it's downstreams (distro, kubuntu in your case) choice what to deem "usable" and to dump it onto their users.

Right away, as long as the multiple issues reg. https://bugs.kde.org/show_bug.cgi?id=341497 (it's NOT a kwin bug) exist, KDE 5 is no way good for productive use. Period (and I tell that everyone asking)
The bug has killed my ksmserver (ie. the session, bye all unwritten data)
Beyond that issue, KDE/5 is getting more mature, but there're still issues (though also imrpovements) compared to SC/4 - it *is* good for everyday use and testing, notably if you're developing in that area, but atm. not for production.

kxkb is unrelated (though claimed not robust either, I've no experience itr, sorry) to kglobalaccel and khotkeys (custom shortcuts) work on top of kglobalaccel.
The major problem with the customized shortcuts is their configuration - it can randomly get erased or loose entries because of the linked bug. As long as you don't touch the config (including shortcuts to applications), there's no (major) problem.

For clarification: it's "upstreams" (KDE/Qt/gilbc/...) job to provide usable software, but it's downstreams (distro, kubuntu in your case) choice what to deem "usable" and to dump it onto their users.

Got that. Did you mean it as an answer to my questions:

How do I know whether it is a KDE or a Kubuntu or an Ubuntu problem?
Which of these problems belong to Kubuntu but not to KDE?

?

Yes.
If you want bugs fixed, ask KDE developers (and use the bugzilla search to check whether it's been reported any maybe fixed, please
If you want to state that distro foo should not ship bar or tag it as beta, ask distro foo.

OK.

Back to work:

6. Watching a video ...

Try on suspended compositing (SHIFT+Alt+F12) and paste the outputs of
- glxinfo

https://paste.kde.org/p8fk5jhoh

- qdbus org.kde.KWin /KWin supportInformation

https://paste.kde.org/pym0usndh

- /var/log/Xorg.0.log

https://paste.kde.org/phjoig65c

supportInfo without suspended compositor, please (sorry if that wasn't clear)

wild guesses would be explcit fencing or a broken buffer queue, try

Code: Select all

KWIN_USE_BUFFER_AGE=0 KWIN_EXPLICIT_SYNC=0 kwin_x11 --replace &


to point 8. (After login it takes up to 90 seconds until everything works, the taskbar being the last. In Kubuntu 15.04 it was just a few seconds)

the problem is probably legated to BT adapter and plasma networkmanager, the problem persists also on machines without BT Adapter
see https://bugs.kde.org/show_bug.cgi?id=354230 and attachment fix 95144
But i then had a second delay up to 23-30 seconds
I lived with that and installed plasma 5.4.3 from kubuntu backports ppa hoping it resolved the 20 second latency. But it didn't.
Further investigating i suspected the akonadi-framework
i trayed: sudo apt-get remove akonadi-server ... didn't resolve
sudo apt-get install akonadi-server ... did resolve the second delay
Kubuntu 15.10 login is now very fast