Implement workaround for upstream problem in CPython

pshmem/shmem.py

@@ -9,7 +9,15 @@
 
 import numpy as np
 
-from .utils import mpi_data_type, random_shm_key
+from .utils import (
+    mpi_data_type,
+    random_shm_key,
+    remove_shm_from_resource_tracker,
+)
+
+# Monkey patch resource_tracker.  Remove once upstream CPython
+# changes are merged.
+remove_shm_from_resource_tracker()
 
 
 class MPIShared(object):

pshmem/utils.py

@@ -6,6 +6,8 @@
 
 import random
 import sys
+# Import for monkey patching resource tracker
+from multiprocessing import resource_tracker
 
 import numpy as np
 
@@ -62,3 +64,25 @@ def random_shm_key():
     # Seed with default source of randomness
     random.seed(a=None)
     return random.randint(min_val, max_val)
+
+
+def remove_shm_from_resource_tracker():
+    """Monkey-patch multiprocessing.resource_tracker so SharedMemory won't be tracked
+
+    More details at: https://bugs.python.org/issue38119
+    """
+
+    def fix_register(name, rtype):
+        if rtype == "shared_memory":
+            return
+        return resource_tracker._resource_tracker.register(self, name, rtype)
+    resource_tracker.register = fix_register
+
+    def fix_unregister(name, rtype):
+        if rtype == "shared_memory":
+            return
+        return resource_tracker._resource_tracker.unregister(self, name, rtype)
+    resource_tracker.unregister = fix_unregister
+
+    if "shared_memory" in resource_tracker._CLEANUP_FUNCS:
+        del resource_tracker._CLEANUP_FUNCS["shared_memory"]