[whouweling]

Yes; gevent does also fix this problem. But it also gives you a lot of new problems when running all requests async. In my experience mostly with views that (in some specific calls, i.e for a specific customer) keep the cpu tied up, for example serializing a lot of data. Random other requests will be stuck waiting and seem slow while it is a lot more difficult to find out which view is the actual problem.

I have deployed applications both under gevent and sync workers in gunicorn and would personally never use gevent again, especially in bigger projects. It makes the behavior of the application unpredictable.

[anentropic]

How does async/await solve this? I would have thought it has exactly the same problem?

[Daishiman]

It does have the same problem. Standard library CPU-heavy functions are not generally async-friendly. You'll be stuck blocking for that 500kb JSON file to serialize.