RuntimeError causes app to stop processing requests

[nvtkaszpir]

Describe the bug
the issues are caused by werkzeug lib,when running python app.py and when doing too much operations/requests then it ends in some race condtition.
This ends with RuntimeError, after which no futher web requests are processed - new connections are accepted but hang indefinetly.

To Reproduce
Steps to reproduce the behavior:

1. python app.py
2. run apache bench/locust whatever (even while true; curl http://127.0.0.1:8080/snapshot;done in 5 terminals should be enough
3. see how app dies after about 15s

Expected behavior
Processing is properly handled, no errors.

Screenshots
No screesnhots

Desktop (please complete the following information):
Ubuntu 22.04 + any browser/curl

Smartphone (please complete the following information):
N/A

Additional context

Possible fix
switch to gunicorn, havent tested but it probably handles this much better but with --worker 1