Bug#1105856: RE: FreeCAD much slower on Debian native than Flatpak version

[Tobias Frost]

Control: fixed -1 1.0.2+dfsg-2

Hi Jelle,

Thanks for providing addtitional information!


On Wed, 15 Oct 2025 19:25:37 +0200 Jelle Haandrikman <jhaand at freedom.nl>
wrote:
> Hi,
> 
> I missed the question about extra information a couple of months ago. 

(My fault, sorry.)

> But I noticed the bug was closed.
> Therefore I reopened the bug and offer extra questions.
> 
> To answer your previous questions.
> 
> > What is your Desktop environment? Are you using Wayland or XOrg?
> KDE Wayland on Debian Trixie.

 
> > When started from console, is there messages there?
> There are no messages.

(When running the Trixie version under wayland, there should be a
message like "Wayland detected …". That's the indication that the
workaround I've mentioned above is used.)

In Trixie we had to have this workaround for wayland, due to a
problem in coin3d where the fix was not ready for Trixie.

There are reports upstream that the workaround might impact 
performance (e.g in https://github.com/FreeCAD/FreeCAD/issues/9273), so
this might be what you are seeing.

> > What is your GPU?
> I have a Radeon RX 7700 XT
> 
> > When you are using Wayland, how are you starting freecad?
> > (because of #1051296, the workaround there might have impact 
> > onperformance)
> 
> I have used both the Debian package and the Flatpak. Using the Debian 
> package makes it worse. Starting via /usr/bin/freecad <model_name>
> 
> You can download the model via.
>
https://github.com/Nicolai-Electronics/tanmatsu-mechanical/blob/main/Tanmatsu_3D-printed.FCStd

I've tried your model with the latest Debian version (1.0.2, unstable,
using a newer opencascade) and compared to the flatpak version, I do get
quit equal performance. Though, I do not the FasternersCmd plugin
installed, (I get a tons of warnings in regards of that when opening
your model)

So I guess you are seeing the wayland / coin3d issue. If that is true,
unfortunatly, I can't really help fixing it, especially as there is 
the workaround using flatpak, this isn't a bug that could be fixed in
stable (Trixie). (and bug fixes are not in scope for backports either,
and backporting coin3d would be only a bug fix, this isn't a viable
route either) 

I'll keep this bug open in case my triaging is wrong, but I'll add a
fixed version 1.0.2+dfsg-2 indication, because this *will* be the first
version that has dropped the workaround. (will, as it has not been
uploaded yet.)

The workaround can be disabled by setting the enviornment value 
QT_QPA_PLATFORM, an empty value should do it; but it will crash on
Trixie/Wayland when opening a Workbench.

> best regards,
> Jelle
> 
> Debian Bug Tracking System schreef op 2025-10-15 18:37:
> 
> > Processing control commands:
> > 
> >> reopen 1105856
> > Bug #1105856 {Done: Tobias Frost <tobi at debian.org>} [freecad]
freecad: 
> > FreeCAD much slower on Debian native than Flatpak version
> > Bug reopened
> > Ignoring request to alter fixed versions of bug #1105856 to the same
> > values previously set

-- 
tobi