Version: 4.7.0 (using KDE 4.7.0) OS: Linux When I'm scrolling through a file with less or vi, sometimes many lines don't paint. When I move the mouse out of the window and the window loses focus, the window repaints with the correct data. I have 'focus follows under mouse' configured. I first discovered this under KDE 4.6.0, but I recently upgraded to KDE 4.7.0 to see if the problem still exists. Xserver is xorg-x11-server-7.6_1.9.3-15.18.4.x86_64 My display card is 'Broadway XT [Mobility Radeon HD 5800 Series]'. If I turn off 'Desktop Effects' with either config menu or ALT-SHIFT-F12, the problem goes away. Additionally, scrolling is slower with Desktop Effects enabled. I have a 11094 line file I created (list of files from the file system). cat'ing this file to the terminal takes approximately 4.5 seconds with desktop effects enabled. cat'ing this file to the terminal takes less than a second with desktop effects disabled. Reproducible: Always Steps to Reproduce: scroll text with less or vi in a xterm Actual Results: Some lines of text are missing, especially near the top of terminal Expected Results: All lines of text shall be displayed
- Please also have a look at bug #264259 Compare the "show paint" results on your side. (settings in "kcmshell4 kwineffects") - This only happens with OpenGL but not with XRender, i assume? - Do you have the blur effect and/or v'syncing enabled? Is it any related? - What if you keep compositing active but disable all effects? - Are *only* terminals affected? - What about other terminals but XTerm? Like konsole, aterm, lxterm or gnome-terminal or whatever. A performance regression through the indirection and (in the GL case) pixmap -> texture conversion is unavoidable. This also heavily depends on your HW and drivers. The XRender backend doesn't have to convert and might be in advance here. Look forward to wayland. However we hope to have improved damage event handling performance in 4.8 (current git master)
I changed OpenGL to XRender and didn't immediately see the issue. I'll run it for a few days and see. cat'ing the file to screen still took about 4 to 5 seconds in the two runs I performed. I'll have to read through bug #264259 more carefully to understand the 'show paint' request. I first noticed the issue when I upgraded my OS distro version which upgraded kde from 4.4.4 to 4.6.0. I'll have to experiment with the different effect settings. I did not set any of them or knew of their existence. I'll try the other terminals as well.
any news?
konsole is unaffected by desktop effects on or off. The other terminal programs are not installed.
Ok, have you meanwhile inspected the "showPaint" results? Is this still an issue with more recent xterm version at all?
I'm running kde 4.7.2 with xorg-x11-server 7.6 and xterm-276-3.2 and I don't notice the issue. The default on this version is with desktop effects disabled. I enabled desktop effects, and still did not notice the issue.
I have the same problem for a loooong time now and I can reproduce it. KDE 4.7.4 from debian experimental. Problem exists for more than a year IIRC. Info: Radeon Hd4870, opensource driver, KMS. xorg radeon driver: 6.14.3 mesa: 7.11.1 kernel: 3.1.5 libdrm: 2.4.27 xorg: 1.11.2.901 (1.11.3 RC1) To reproduce: Open a terminal (xterm or rxvt - with rxvt seems to be more often - may by my imagination) and open a text file in vi. Then press ctrl-l to refresh the screen. To me, it happens every second refresh. At first it may need more that one to have parts of the screen disappear. If I move the window it gets repainted correctly.