Closed
Description
Environment
- Pythonnet version: 2.5.2
- Python version: issue verified on 3.7.2, 3.7.7 and 3.8.6
- Operating System: Windows 10 64bit
- .NET Runtime: .NET Framework 4.7.2
Details
Hello everybody and thanks for this great piece of Software!
The basic issue is:
- if I throw a .NET exception from within C# code
- and the exception moves into the python space
- i.e. the C# method was called from python
- then the memory of the exception does not get released anymore
This becomes apparent when you throw quite a lot of exceptions and your applications runs 24/7.
Reproducability
The issue is fairly easy to reproduce. I have also setup a sample repository, which reproduces the issue.
https://github.com/Rookfighter/pythonnet-memleak-exceptions
The basis instruction are:
- setup a Visual Studio Project of the type "Class Library .NET Framework 4.7.2"
- create a
ExceptionThrowerclass
using System;
namespace LeakingExceptions
{
public class ExceptionThrower
{
public void ThrowException()
{
throw new Exception("a simple exception");
}
}
}- create a python script which imports the assembly
- create a
ExceptionThrowerobject and callThrowExceptionwithin a loopedtry exceptblock
import os
import __main__
import clr
# bin dir must be adjusted to your relative path!
bin_dir = os.path.abspath(os.path.join(os.path.dirname(__main__.__file__), '../Source/LeakingExceptions/bin/Debug'))
clr.AddReference(os.path.join(bin_dir, 'LeakingExceptions'))
from LeakingExceptions import ExceptionThrower
thrower = ExceptionThrower()
while True:
try:
thrower.ThrowException()
except:
pass- in the task manager you can then watch the application to accumulate memory and never release it
