Please add keep_alive information and corresponding constants (5 seconds, 512 connections to the documentation)

done

Code looks good to me.
Please add the corresponding changelog entry.
Also there are several commits about node flags. Do they relevant for your change?

Please add the corresponding changelog entry.
Done
Also there are several commits about node flags. Do they relevant for your change?
Rebase glitch, should be fixed now

void Connection::start()
29 {
30 TCP_socket.async_read_some(
31 boost::asio::buffer(incoming_data_buffer),
32 strand.wrap(boost::bind(&Connection::handle_read,
33 this->shared_from_this(),
34 boost::asio::placeholders::error,
35 boost::asio::placeholders::bytes_transferred)));
36
37 if (keep_alive)
38 {
39 // Ok, we know it is not a first request, as we switched to keepalive
40 timer.cancel();
41 timer.expires_from_now(boost::posix_time::seconds(keepalive_timeout));
42 timer.async_wait(std::bind(
43 &Connection::handle_timeout, this->shared_from_this(), std::placeholders::_1));
44 }
45 }
46
47 void Connection::handle_read(const boost::system::error_code &error, std::size_t bytes_transferred)
48 {
49 if (error)
50 {
51 return;
52 }
53
54 if (keep_alive)
55 {
56 timer.cancel();
57 timer.expires_from_now(boost::posix_time::seconds(0));
58 }

I wonder the keepalive whether work since you set expire_from_now in start() then expires_from_now in handle_read(), but every start() will execute handle_read()

@akashihi @gardster

void Connection::handle_read(const boost::system::error_code &error, std::size_t bytes_transferred)
48 {
49 if (error)
50 {
51 return;
52 }
53

when read some bytes error, why not execute handle_shutdown right now?

when read some bytes error, why not execute handle_shutdown right now?

This was added recently to fix a file exhaustion issue - see #6112