Keep Alive

http://stackoverflow.com/questions/1787557/apache-proxy-to-tomcat-keep-alive-confusion
 

keep-alive 옵션에 대한 설명.


There are (at least) four “keep-alive”s.

1. HTTP layer keep-alive between client browser and Apache. (Enables multiple client requests in a HTTP/TCP connection. “KeepAlive” directive to configure.)

2. TCP layer keep-alive between client browser and Apache. (To avoid connection to be closed by firewalls, send empty packet periodically (around 2 hours by default in Linux). I don't know how to configure in Apache.)

3. AJP layer keep-alive between Apache and Tomcat. (Enables multiple Apache request in a AJP/TCP connection. “max” and “smax” options for “ProxyPass” to configure.)

4. TCP layer keep-alive between Apache and Tomcat. (Same as 2, but for firewall between Apache and Tomcat. “keepalive” option for “ProxyPass” directive to configure.)