In an application where we were handling incoming requests in new threads, we noticed that the memory usage grew over time. After trying to understand what's going on, i was able to reproduce this with a smaller python script that i've attached.

What we do:
- start a thread
- the thread allocates some memory
- at some point later we join the thread

Notice that this seems to be more like a race-condition because it doesn't reproduce without adding some delays between the creation of different threads. I've added a comment in the file that basically commenting one time.sleep makes the leak to not reproduce anymore.

On the other side, I was able to reproduce this consistently with every version of python on mulitple systems but only on Linux. On windows it doesn't reproduce.