web server written in werkzeug has memory leak under python 11.0

[ochinchina]

Description

The memory of web server written in Werkzeug will keep increasing if it is deployed to python 11.0 and tested with performance testing tool ab

How to replicate the bug:

write a simple web server with following code and start it:

from werkzeug.wrappers import Request, Response

@Request.application
def application(request):
    return Response("Hello, World!")

if __name__ == "__main__":
    from werkzeug.serving import run_simple
    run_simple("0.0.0.0", 5000, application)

test it with ab tool:

$ ab -n 10000 http://127.0.0.1:5000

after executing above command, almost the memory of the web server will increase every time and never decrease.

Expected behavior

the memory of above web server should not keep increasing.

Environment:

• Python version: 11
• Werkzeug version: 2.2.2

[davidism]

The web server is Python's http.server. Please report a bug there instead. Possibly a duplicate of python/cpython#99205.