Keep Connections Alive : Browser - Load Balancer - Web Server - mod jk - Tomcat : Part 3

This series is about how connections are kept alive between different components along the route.
 Browser - Load Balancer - Web Server - mod jk - Tomcat

Part 1 : Browser - Load Balancer.
Part 2 : Load Balancer - Apache HTTP Server
Part 3 : Apache HTTP Server - Mod jk
Part 4 : Mod jk - Tomcat

Apache Web Server - Mod jk

Does mod_jk changes how Apache web server handles its connection with the clients?

Mod jk is a module that runs within the Apache web server. Apache web server will manage the connections between itself and the clients, usually web browsers or a load balancer, and pass the request to a chain of modules.

Using the example described in an Apache module tutorial, a module will register a hook with the web server and the web server will pass a request_rec to the module.

//register the hook

static void mod_tut1_register_hooks (apr_pool_t *p)
{
  ap_hook_handler(mod_tut1_method_handler, NULL, NULL, APR_HOOK_LAST);
}

//The hook takes a parameter as request_rec

static int mod_tut1_method_handler (request_rec *r)
{
  fprintf(stderr,"apache2_mod_tut1: A request was made.\n");
  fflush(stderr);
  return DECLINED;
}

The Answer 

For the purpose of this article, the point is mod jk doesn't have the chance to meddle with the socket between web server and clients, for example, by setting additional keep-alive parameters. 

More Things to Consider

The connection between mod_jk and Tomcat Servers is discussed in part 4 of this topic.