KST cpu hog (100%) on Gnome natty/lucid
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
kst (Ubuntu) |
Invalid
|
Undecided
|
Unassigned |
Bug Description
As I don't have the possibility right now to register an account at KDE Bug Tracking System, I'll try posting here.
I tried using Kst plot on Natty; I cannot remember if I could install the vanilla Lucid version on Natty - but eventually, I tried the Lucid version of the latest 2.0.7 ppa on both Natty and Lucid; and then I also built tag 2.0.7 from git source on Natty. And in all these cases, `kst` starts up fine; e.g. `top` reports:
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1101 root 20 0 54272 22m 10m S 4 1.1 128:41.95 Xorg
4475 user 20 0 79428 26m 20m S 1 1.4 0:01.11 kst2
... (if kst2 even makes the `top` list) - but as soon as you put an empty plot in the window, CPU usage goes to nearly 100%; e.g. `top` reports:
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
4475 user 20 0 79428 27m 21m R 97 1.4 0:24.87 kst2
1101 root 20 0 56756 22m 10m S 93 1.1 129:16.00 Xorg
... and this is regardless if Pause in interface is clicked (this is adding an empty plot after startup, after all - before any data is loaded); I had OpenGL activated - and so the CPU is not exactly 99% but a little less, as above - but still, it's impossible to do anything with that after all.
Since I tried both ppa and source-built versions, I guess the fault is not with `kst` itself, but with whatever Gnome-Qt bridge my systems are using; but I thought it'd be best reported here first. Not sure if it helps, but on natty I have:
$ qmake --version
QMake version 2.01a
Using Qt version 4.7.2 in /usr/lib
I tried to run `kst2` a bit under `ltrace`, and can see massive output as soon as the CPU hog starts; messages like:
....
_ZNK11QMetaObje
_ZNK11QMetaObje
_ZNK13QGraphics
_ZNK17QGraphics
_ZNK11QMetaObje
_ZNK11QMetaObje
_ZNK13QGraphics
_ZNK17QGraphics
_ZN12QApplicati
_ZN11QMainWindo
_ZThn8_
_ZThn8_
_ZThn8_
_ZThn8_
_ZThn8_
_ZNK7QWidget6me
_ZNK7QWidget6me
_ZNK7QWidget6me
_ZNK7QWidget6me
<... _ZNK7QWidget6me
<... _ZNK7QWidget6me
<... _ZNK7QWidget6me
<... _ZThn8_
_ZThn8_
_ZN12QApplicati
....
... looping all the time - so I guess this supports some problem with Qt libraries.
I'm aware this is a report for now obsolete versions of Ubuntu, but I thought it'd be best if it is logged; hope that's ok,
Cheers!
Forgot to say - what _does_ work for me, on natty at least, is - somewhat ironically - installing the Windows version of `kst` under `wine` (!) No CPU hog, and pretty decent responsivity - so that's what I'm using... Though - of course - given that the source seems to build nicely and all, of course I'd prefer to use a native build instead...