Wacom's message queue puts CPU to 100%

[Preben S]

Rev. 20535 and earlier on XP.

When the node tool is active, and a path with many nodes selected, only a few of it's nodes are displayed on the screen.
The CPU goes into ~100% activity without anything more happening before the cursor is moved outside the Inkscape window (or waiting VERY long time).
Using ctrl-A to select all these nodes also goes extremely much faster, when the cursor is outside the Inkscape window.
Even when nothing is selected, the CPU goes on high activity, when the cursor is in the window.
Removing the mouse/pen from the tablet makes the same change on effectivity as moving the cursor outside the window.

There has been some notes in the past on patching gtk+ to limit the Wacoms message rate, and I also got the impression that the problem was solved permanently in gtk+.
But this is apparently not the case.
Whatever, if this bug is considered to be in in gtk+ or Inkscape, it is really a showstopper, if you are not aware of the reason and what to do.

[jazzynico (jazzynico)]

Not reproduced on Vista, Inkscape 0.47.

Could you please confirm you still have this issue with 0.47?
If so, could you test a snapshot at http://inkscape.modevia.com/win32/?M=D (the Windows devlibs, including gtk+, have been updated recently)?

Thanks!

[Preben S (prsodk)]

The perforrnance has been improved significantly.
It seems to work without the bug now.

[su_v (suv-lp)]

@Preben - which Inkscape version / revision did you use to test the performance?

[Preben S (prsodk)]

R9207 on XP

[Preben S (prsodk)]

I'm sorry, but my tests was not comprehensive enough.

The bug is still there, the performance has however been improved somewhat.

[jazzynico (jazzynico)]

Reproduced on Windows XP, Inkscape 0.47, 0.48.1 and trunk revision 10958.
The CPU activity is not 100% but significantly higher than expected (~65%).
Using the mouse instead of the tablet to perform the same action (select lots of nodes and let the cursor on the path) doesn't lead to such a CPU consumption.

Also reproduced on Ubuntu 11.04, trunk revision 10958.

[jazzynico (jazzynico)]

Also reproduced with Gimp, but to a lesser extend (no CPU activity with the mouse, about 20% with the tablet).
May well be a gtk issue, or a communication issue between the tablet and the application.