mod_cgid (Webmaster in a Nutshell, 3rd Edition)

19.10. mod_cgid

On systems which use a multithreaded MPM module, mod_cgid automatically replaces mod_cgi, creating an external script processing daemon to execute CGI scripts. This saves the server system from spawning a new process to handle a CGI request, which greatly increases system load. The server communicates to the script daemon via Unix domain socket specified with the ScriptSock directive. Otherwise, this module is the same as mod_cgi. Apache 2.0 and up.

ScriptSock

ScriptSock socket

[server config, or within <VirtualHost>]

Specifies the name of the socket that connects to the CGI daemon. The server's permissions are used to open the socket.