David Kimura PRO said about 8 years ago on ActionCable on Production :

No, `max_conns` is the maximum number of file descriptors that can be open where as `max-persistent-conns` is the maximum number of persistent connections you're referring to. Depending on your configuration, you could have a dedicated web socket server balanced by an HAPROXY server. This would allow for much greater number of connections while all serving at the same endpoint.