python thread blocking main thread

[luis605]

Hello there! I'm working on acquiring and releasing the GIL correctly using tbb from Intel. However, it seems that the Python thread is blocking the main thread. I'm wondering if this is normal or if it's a fault of GIL. I've searched through many posts, blogs, questions, and discussions, but I haven't found a solution to fix it with my code.

This is my code:

    void runScript()
    {
        if (script.empty()) return;

        py::gil_scoped_acquire acquire;
        py::module entity_module("entity_module");
        py::class_<Entity>(entity_module, "Entity")
            .def(py::init<>())
            .def_readwrite("name", &Entity::name)
            .def_readwrite("position", &Entity::position)
            .def_readwrite("scale", &Entity::scale)
            .def_readwrite("rotation", &Entity::rotation)
            .def_readwrite("color", &Entity::color)
            .def_readwrite("visible", &Entity::visible)
            .def_readwrite("collider", &Entity::collider);

        py::object entity_obj = py::cast(this);
        py::module input_module = py::module::import("input_module");
        py::module collisions_module = py::module::import("collisions_module");
        py::module camera_module = py::module::import("camera_module");

        auto locals = py::dict("entity"_a=entity_obj,
                            "IsMouseButtonPressed"_a=input_module.attr("IsMouseButtonPressed"),
                            "IsKeyDown"_a=input_module.attr("IsKeyDown"),
                            "KeyboardKey"_a=input_module.attr("KeyboardKey"),
                            "raycast"_a=collisions_module.attr("raycast"),
                            "camera"_a=py::cast(&camera));



        try
        {
            string script_content = read_file_to_string(script);

            py::gil_scoped_acquire acquire;

            auto execute_script = [&script_content, &locals]() {
                py::exec(script_content, py::globals(), locals);
            };

            // Create a TBB task group
            tbb::task_group tg;

            tg.run(execute_script);

            // Wait for all the tasks to complete
            tg.wait();


        } catch (const py::error_already_set& e) {
            py::print(e.what());
        }

        py::gil_scoped_release release1;

    }

I also tried async and using a normal pthread but no luck, that is why I tried tbb

[luis605]

Closing for inactivity

[AlexanderSerov]

1. Can't understand goal of this code. You mix multiple concepts and almost every concept is misused. Start from the docs
2. Give full example including CMakeScripts.txt, python side code, and c+ side including includes.

[luis605]

Hi there. I found out what was causing the issue some while ago and with a bit of modification it seems to be working now. Thank you

[matrixbot123]

Hi there. I found out what was causing the issue some while ago and with a bit of modification it seems to be working now. Thank you

How did you solve this

[luis605]

It seems I was setting up GIL wrongly when creating threads and also setting up it wrongly in the runScript() function. I fixed the issue after 3 days of trying and failing and eventually succeeding. It was just how I was acquiring and releasing Gil. First release and then acquiring seems to be how we should initialize GIL and finally release it.