Enable threaded mode. Allows concurrent requests to controller actions and multiple database connections. Also disables automatic dependency loading after boot, and disables reloading code on every request, as these are fundamentally incompatible with thread safety.
# File railties/lib/initializer.rb, line 892 def threadsafe! self.preload_frameworks = true self.cache_classes = true self.dependency_loading = false self.action_controller.allow_concurrency = true self end