Ok thanks.
Problems on Installing IfcOpenShell was noted also here in jan 2022:
https://forum.freecadweb.org/viewtopic.php?t=65699
Hope it can help to troubleshooting.
This may help for those missing ifcopenshell: https://blenderbim.org/docs-python/ifcopenshell-python/installation.html
To test multicore, do import multiprocessing then multiprocessing.cpu_count()
At the end, even if on Ubuntu (20.04 LTS) repos “IfcOpenShell” was NOT present, I simply installed “python3-pip” package and then IfcOpenShell via pip, so:
sudo apt install python3-pip && pip install ifcopenshell
Done 
Is there an error message in the FreeCAD console?
No, only system (OS) package manager crash notification. Maybe because he tried “apt install ifcopenshell” but there is no package on repos?
It’s working 
=> 12 seconds on my Ryzen 7 with 16 core
For information, I have been using AppImage on my Fedora for a couple of years, no need to separately install IfcOpenshell.
And difference in version, no branch information required here
OS: Fedora Linux 36 (Workstation Edition) (GNOME/gnome)
Word size of FreeCAD: 64-bit
Version: 0.21.30345 (Git)
Build type: Release
Branch: master
Hash: f42a47aa0fd8c4f34ef63c185d9f29b9b6e84737
Python 3.10.6, Qt 5.15.4, Coin 4.0.0, Vtk 9.1.0, OCC 7.6.3
Locale: English/United States (en_US)
Installed mods:
* dodo 1.0.0
* DynamicData 2.46.0
* ArchTextures
* Another link to SketchArchLite
* BOLTSFC.backup1666323893.5041647
* BOLTSFC
* FreeCAD-BlenderBIM.backup1666328110.015535
* FreeCAD-BlenderBIM
Thanks, works here on my i3
Then, what is difference with ‘multicore’ and some codes in Yorik’s github needs changes ?
>>> import multiprocessing
>>> multiprocessing.cpu_count
<bound method BaseContext.cpu_count of <multiprocessing.context.DefaultContext object at 0x7f058efdd810>>
>>> multiprocessing.cpu_count()
4
>>>
Cool
chennes i’m having ifcopenshell installation problems via the addon manager. Will report back soon.
Installing via addon manager FreeCAD hangs (with an inability to press ‘Cancel’ in the dialog
CLI output:
pip timed out
Noneb'pip 22.3 from /snap/freecad/375/lib/python3.8/site-packages/pip (python 3.8)\n'pip 22.3 from /snap/freecad/375/lib/python3.8/site-packages/pip (python 3.8)
Traceback (most recent call last):
File "/snap/freecad/375/usr/Mod/AddonManager/addonmanager_workers_installation.py", line 399, in run
self._install_python_packages()
File "/snap/freecad/375/usr/Mod/AddonManager/addonmanager_workers_installation.py", line 434, in _install_python_packages
self._install_required(vendor_path)
File "/snap/freecad/375/usr/Mod/AddonManager/addonmanager_workers_installation.py", line 470, in _install_required
proc = subprocess.run(
File "/snap/freecad/375/usr/lib/python3.8/subprocess.py", line 516, in run
raise CalledProcessError(retcode, process.args,
subprocess.CalledProcessError: Command '['/snap/freecad/375/bin/python3', '-m', 'pip', 'install', '--disable-pip-version-check', '--target', '/home/beast/snap/freecad/common/AdditionalPythonPackages', 'ifcopenshell']' returned non-zero exit status 1.
OS: Ubuntu Core 20 (KDE/plasma)
Word size of FreeCAD: 64-bit
Version: 0.21.30711 (Git) Snap 375
Build type: Release
Branch: master
Hash: 916891c3fc1855b210e826825c235d8c96b78456
Python 3.8.10, Qt 5.15.5, Coin 4.0.0, Vtk 7.1.1, OCC 7.6.3
Locale: English/United States (en_US)
Can you run the command manually:
/snap/freecad/375/bin/python3 -m pip install -v --disable-pip-version-check --target /home/beast/snap/freecad/common/AdditionalPythonPackages ifcopenshell
… and let me know what the output is? Note I added a -v verbose flag.
$ /snap/freecad/375/bin/python3 -m pip install -v --disable-pip-version-check --target /home/beast/snap/freecad/common/AdditionalPythonPackages ifcopenshell
bash: /snap/freecad/375/bin/python3: No such file or directory
i also did install the addon and did successfully open an ifc model, however there was no pop up dialog to chose a importer.
OS: Windows 10 Version 2009
Word size of FreeCAD: 64-bit
Version: 0.21.30492 (Git)
Build type: Release
Branch: master
Hash: b4578fb3eae842eb510a1bc055d07d369a67ce94
Python 3.10.6, Qt 5.15.4, Coin 4.0.0, Vtk 9.1.0, OCC 7.6.3
Installed mods:
* FreeCAD-BlenderBIM 2022.10.20
Do Snaps move/change the path (e.g. is that 375 constant)?
It’s dynamic. Looks like this is relevant to 6707
This should be pretty easy to fix in the Addon Manager, I’ll try to get to it later today.
ETA : if you have a minute can you make an issue and assign it to me?
yorik Moult
I just update the add-on and try to import the same ifc again, unfortunately FC crash after a while for a few time (the import also make my pc sluggish) Trying to see if I can catch some log.
Oh, after a few attempt, this time it import in 1:59 min, file size in *.FCStd is similar, about 13mB 
It seems the UI is slightly less responsive ?
Thanks for the confirmation
Seems you import in about 2 min, can you indicates your PC / CPU configuration please.