pvpython freezes when run in headless environment
Hi all. I am currently facing a strange issue when using pvpython
. More specifically, we have a custom script which saves/build some Paraview states that "freezes" (aka do not terminate) under certain conditions.
We are using Ubuntu 16.04 on Travis CI and ParaView 5.6.0. In order to provide a graphical interface on the Travis build, we are using xvfb. You can find the script which is giving us these headaches here: https://github.com/BioDynaMo/biodynamo/blob/master/src/core/visualization/generate_pv_state.py
The commands used to reproduce this error are:
mkdir -p output/test
mv simulation_info.json output/test
pvpython generate_pv_state.py output/test/simulation_info.json
and you can find the simulation_info.json
file attached here simulation_info.json.
This python script usually works without errors. However, we have noticed that on Travis CI the script just hangs. The only way then to kill it is by Ctrl+C. By looking a bit into it (by using pdb or strace) it seems like this behaviour is caused by some kind of locking issue but I was not able to find anything else.
I also googled a bit and searched in the past issues but I found nothing.
What do you think it could be the cause? I will be happy to provide more information such to solve this problem.