Understanding multi threading support #59

Activity

1. dawnrs commented on Nov 18, 2021

   

   dawnrs

   on Nov 18, 2021

   Last edited by dawnrs

   More actions

   The text below just is my own experience of pythonqt and I can not make sure everything is right.
   If you use the C++ thread to run python codes, you need to keep a PythonQtGILScope object when python function is running because of the fucking GIL.
   If you just want to use the python thread，the thread can work well except some extra features.
   There is a example:

   {
       // this is a child thread.
       {
           PYTHONQT_ALLOW_THREADS_SCOPE;
           {
               PYTHONQT_GIL_SCOPE;
               {call a python code which create a python thread}
               //In this scope, you can call a python function and also can create a python thread.
   
               {call another python codes or functions}
               // In this time, the python thread will work.
   
               {some C++ codes} 
               // In this time, the python thread will sleep.
           }
           {some C++ codes}
           //In this scope, python thread is still working
   
           {call a python function}
           //this behavior will cause a error from python.dll
       }
       {some C++ codes}
       //If python thread do not finish its work,  it will sleep and when the code run into the PYTHONQT_ALLOW_THREADS_SCOPE again, it will be invoked.
   }
   
2. AaronLin295160370 commented on Mar 2, 2022

   

   AaronLin295160370

   on Mar 2, 2022

   More actions

   被GIL整崩溃了，无法支持多线程，而且没有调试功能，pdb无法在pythonqt上独立运行，只有参照bdb源码写一份c++调试代码，但是依旧无法解决多线程GIL, 想绕过GIL使用启用多进程，结果傻眼了，直接开启了多套程序
3. mrbean-bremen

   added

   questionFurther information is requestedFurther information is requested

   on Nov 9, 2023
4. MeVisLab

   locked and limited conversation to collaborators on Dec 15, 2023
5. mrbean-bremen

   converted this issue into a discussion #171 on Dec 15, 2023