Threaded Web COMP sounds interesting, but it’s slightly different from wanted answer.
Finally I noticed.
Using concurrent.futures.ProcessPoolExecutor, above error happened.
Using concurrent.futures.ThreadPoolExecutor or threading, no error.
also Is it not recommend in TouchDesigner?
If not, I will use OSC, after dividing python process to other application.
It seems like for the process pool it’s trying to launch another TouchDesigner process, not another python interpreter process. We’ll have to look at how we have our python integration setup so it potentially starts up the correct standalone interpreter for the process pool instead of trying to start up another TouchDesigner process.