From 0e0d86f6d8b087a6a43d18c835607643d8e8d116 Mon Sep 17 00:00:00 2001
From: allegroai <>
Date: Mon, 10 May 2021 20:33:30 +0300
Subject: [PATCH] Fix python3.8 race condition in task.close()

---
 clearml/task.py                 |  4 ++--
 clearml/utilities/process/mp.py | 10 +++++++---
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/clearml/task.py b/clearml/task.py
index 7d3bde95..16d0f240 100644
--- a/clearml/task.py
+++ b/clearml/task.py
@@ -1396,7 +1396,7 @@ class Task(_Task):
             self.__register_at_exit(None)
             if not is_sub_process:
                 # make sure we enable multiple Task.init callas with reporting sub-processes
-                BackgroundMonitor.clear_main_process()
+                BackgroundMonitor.clear_main_process(self)
                 # noinspection PyProtectedMember
                 Logger._remove_std_logger()
 
@@ -3050,7 +3050,7 @@ class Task(_Task):
 
         # make sure no one will re-enter the shutdown method
         self._at_exit_called = True
-        BackgroundMonitor.wait_for_sub_process()
+        BackgroundMonitor.wait_for_sub_process(self)
 
     @classmethod
     def __register_at_exit(cls, exit_callback, only_remove_signal_and_exception_hooks=False):
diff --git a/clearml/utilities/process/mp.py b/clearml/utilities/process/mp.py
index 21d08ec3..c4759154 100644
--- a/clearml/utilities/process/mp.py
+++ b/clearml/utilities/process/mp.py
@@ -414,8 +414,8 @@ class BackgroundMonitor(object):
         return bool(cls._main_process)
 
     @classmethod
-    def clear_main_process(cls):
-        cls.wait_for_sub_process()
+    def clear_main_process(cls, task):
+        cls.wait_for_sub_process(task)
         BackgroundMonitor._main_process = None
         BackgroundMonitor._parent_pid = None
         BackgroundMonitor._sub_process_started = None
@@ -423,9 +423,13 @@ class BackgroundMonitor(object):
         SingletonThreadPool.clear()
 
     @classmethod
-    def wait_for_sub_process(cls, timeout=None):
+    def wait_for_sub_process(cls, task, timeout=None):
         if not cls.is_subprocess_enabled():
             return
+
+        for d in BackgroundMonitor._instances.get(id(task.id), []):
+            d.stop()
+
         tic = time()
         while cls.is_subprocess_alive() and (not timeout or time()-tic < timeout):
             sleep(0.03)