Multithreaded Django runserver is not documented in 1.4 release notes

[onyxfish]

I stumbled across the new --nothreading option. It says to read more in the release notes, but this isn't mentioned in the release notes. This really tripped me up when a threading bug appeared in development code where I did not think such a thing was possible.

​https://docs.djangoproject.com/en/dev/ref/django-admin/#django-admin-option---nothreading

[valhallasw]

This really should be added to the release notes -- the server fails with too many concurrent connections, and new connections are RST'ed. ("apr_socket_recv: Connection reset by peer (104)" according to ab - the nginx running in front returned 502's to the browser). Running the server with --nothreading means everything works as it did before. As this was not noted in the release notes, it took me an hour or two to find out what was causing this.

[Anssi Kääriäinen]

I guess it is too late to change the default, so adding a note about this to release notes seems like the correct way forward.

I will close this as duplicate of #17997.