konsole getting slower

[Bernhard Schmidt]

Binary package hint: konsole

I'm running Kubuntu Jaunty. I'm doing most of my work in konsole, mostly using tabs.

Ever since I upgraded from Intrepid I observe that konsole is getting slower and slower after a few hours of work have passed. I can feel a slight lag (only a few 100ms, but annoying as hell) when changing between tabs or changing the screen content (changing into another channel in irssi). Same when cat'ing a large textfile, it is fast and smooth after login but gets pretty sluggish after a few hours.

It is probably not related to Bug #343714 since my memory consumption appears to be normal, there is plenty of RAM free or used as disk cache, also only a few MB of the swap is used.

Restarting konsole completely (I made sure no konsole process was left running) doesn't help, logging out and in again does. So far I have experienced the problem on three different machines, all running Jaunty

Dell Latitude D630, G965, EXA, Desktop Effects
Dell OptiPlex 760, Q45/43, UXA, Desktop Effects
self-made ASrock 780G-based (radeon-driver), EXA, no Desktop Effects

I think the OptiPlex got better after I switched to UXA, hard to tell. Also I can't rule out that other KDE parts or the whole system are affected, konsole is just what I'm using most, so I can compare the performance there.

Systems are up to date.

bschmidt@lxbsc02:~$ lsb_release -rd
Description: Ubuntu jaunty (development branch)
Release: 9.04

ii konsole 4:4.2.2-0ubuntu1 X terminal emulator for KDE 4

[Laurent Bonnaud (laurent-bonnaud)]

I have a similar problem with konsole in jaunty:

 - scrolling a konsole is very slow: the scrollbar needs more than 1s to catch up with the pointer position
 - using page-up/down in less is also very slow: the text needs 1s to display

I use this graphic card:

01:00.0 VGA compatible controller: ATI Technologies Inc M56P [Radeon Mobility X1600]

with the free ati/radeon driver.

Enabling or disabling desktop effects in KDE4 does not change konsole's speed.

I used konsole 4.2 in intrepid and did not have this problem (with the fglrx driver).

The X server does not seem to be responsible for this problem because gnome-terminal is very fast for the same tasks.

[Laurent Bonnaud (laurent-bonnaud)]

I think that I have found what triggers this bug:

 - when I boot my computer, konsole is fast
 - when I restart the X server, konsole is fast again
 - however, when I suspend to RAM and resume the computer, konsole is immediately noticeably slower

Bernhard, do you also observe that suspend+resume slows konsole down ?

[Bernhard Schmidt (berni)]

I can definitely confirm the first two, but I'm not so sure about suspend+resume. The only system I regularly suspend is my laptop, and I don't think it is getting worse doing that. Not getting better either.

Oh, and the GNOME desktop (or alternative terminals like xterm) run just fine.

[ieL3kudohg (iel3kudohg-deactivatedaccount)]

I also see this slowness, but it appears to be there as soon as I log in.

Login, start konsole, maximise the window (the bigger the window, the slower it is), run top and set the update period to 0.2 seconds (i.e. something to generate a lot of text activity). Doing this, the Xorg process hovers around 50% CPU usage. In xterm, and to a lesser extent gnome-terminal, Xorg usage is normal and barely registers.

I've not bothered running konsole for long enough to see if it gets worse, and I don't use suspend/resume.

I'm using the nvidia 180 driver package. Performance everywhere else seems fine.

[keram (marek-sierka)]

I can definitely confirm that my system is slow after suspending to RAM and resuming the computer. After booting everything is OK.

System: Dell D630, GM965/GL960, UXA, 9.04 with 2.6.30-020630rc7-generic

[Laurent Bonnaud (laurent-bonnaud)]

This bug is still in this konsole version: 4:4.2.95-0ubuntu1~jaunty1~ppa1.
Therefore it is probably still in karmic.

[Laurent Bonnaud (laurent-bonnaud)]

For a few days I have been running updated KDE (4.2.96) and Qt (4.5.1) packages from kubuntu and VLC PPA and this bug is fixed. Konsole scrolling is now acceptably fast and remains fast even after a few days of use.

Here are version details:

Package: kdelibs5
Version: 4:4.2.96-0ubuntu2~jaunty1~ppa1

Package: konsole
Version: 4:4.2.96-0ubuntu1~jaunty1~ppa1

Package: libqtgui4
Version: 4.5.1-1~ppa1~jaunty1

Bernhard, can you confirm this and close this bug ?

[Laurent Bonnaud (laurent-bonnaud)]

KDE 4.3 is out and fixes this bug.