> But, I have a question. Can't Apache detect the closed connection as soon > as the backend connection is closed?
It "can" but it doesn't. > I am sorry that I don't review codes yet so I don't know if Apache uses > blocking I/O or NIO for backend. > NIO is a java-ism. mod_proxy is synchronous and nobody is watching the sockets while a thread isn't handling a request and trying to use the conn. > > Is the watcher thread which is going through all of the connections > looking to see if they have been closed by the peer only solution? There is no thread.
