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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"memory leak - simple function call in a loop","articleBody":"I'm getting a memory leak with simple calls from .NET to Python function. The issue is reproducible on all pythonnet versions that I tested. When I test Python calls to .NET, then the memory leak is less obvious, since all resources are released when calling the CPython `gc.collect()`. Calling the same function from .NET does not release any resources, but calling the CLR `GC.WaitForPendingFinalizers()` blocks the execution.\r\n\r\n[memoryleakpykw.zip](https://github.com/pythonnet/pythonnet/files/1293771/memoryleakpykw.zip)\r\n\r\n\r\n```python\r\n\u003e\u003e\u003e import clr\r\n\u003e\u003e\u003e import System\r\n\u003e\u003e\u003e for i in range(20000000):\r\n...   a=System.Double(i)\r\n...\r\n\u003e\u003e\u003e import gc\r\n\u003e\u003e\u003e gc.collect()\r\n```\r\n\r\n`pyinclr.py`\r\n```python\r\ndef testmethod():\r\n\treturn \"abc\"*3\r\n```\r\n\r\n```csharp\r\nusing System;\r\nusing Python.Runtime;\r\n\r\nnamespace memoryleakpykw\r\n{\r\n    class Program\r\n    {\r\n        static void Main(string[] args)\r\n        {\r\n            PyObject pymodule;\r\n            PyObject gc;\r\n            PyObject testmethod;\r\n\r\n            PythonEngine.Initialize();\r\n\r\n            IntPtr pylock = PythonEngine.AcquireLock();\r\n            {\r\n                PyObject sys = PythonEngine.ImportModule(\"sys\");// Py.Import(\"sys\");\r\n                gc = PythonEngine.ImportModule(\"gc\");// Py.Import(\"sys\");\r\n                sys.GetAttr(\"path\").InvokeMethod(\"append\",\r\n                    new PyString(@\"C:\\Users\\denis.akhiyarov\\source\\repos\\memoryleakpykw\\pyinclr\"));\r\n                pymodule = PythonEngine.ImportModule(\"pyinclr\");\r\n                testmethod = pymodule.GetAttr(\"testmethod\");\r\n            }\r\n\r\n            PythonEngine.ReleaseLock(pylock);\r\n\r\n            Console.WriteLine(\"starting test for memory leak, press any key\");\r\n            Console.ReadKey();\r\n\r\n            pylock = PythonEngine.AcquireLock();\r\n\r\n            {\r\n                for (int i=1; i\u003c=1000000; i++)\r\n                {\r\n                    testmethod.Invoke();\r\n                }\r\n            }\r\n\r\n            gc.InvokeMethod(\"collect\"); \r\n\r\n            PythonEngine.ReleaseLock(pylock);\r\n            \r\n            GC.Collect();\r\n            //GC.WaitForPendingFinalizers(); // this blocks execution\r\n            GC.Collect();\r\n\r\n            Console.WriteLine(\"finished test for memory leak, press any key\");\r\n            Console.ReadKey();\r\n        }\r\n\r\n    }\r\n}\r\n```\r\n\r\n\r\n\r\n\r\n","author":{"url":"https://github.com/den-run-ai","@type":"Person","name":"den-run-ai"},"datePublished":"2017-09-11T19:32:06.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":14},"url":"https://github.com/541/pythonnet/issues/541"}