Tuning CGI Stub Processes (UNIX/Linux)

In Web Server, the CGI engine creates CGI stub processes as needed. On systems that serve a large load and rely heavily on CGI-generated content, it is possible for the CGI stub processes to consume all system resources. If this happens on your server, the CGI stub processes can be tuned to restrict how many new CGI stub processes can be spawned, their timeout value, and the minimum number of CGI stub process that run at any given moment.

If you have an init-cgi function in the magnus.conf file running in multi-process mode, you must add LateInit = yes to the init-cgi line.

Tune the following settings to control CGI stubs. These settings are on the configuration's Performance Tab ⇒ CGI sub tab.

• Minimum Stubs Size: Controls the number of processes that are started by default. The first CGI stub process is not started until a CGI program has been accessed. The default value is 0. If you have an init-cgi directive in the magnus.conf file, the minimum number of CGI stub processes are spawned at startup.

• Maximum Stub Size: Controls the maximum number of CGI stub processes the server can spawn. This is the maximum concurrent CGI stub processes in execution, not the maximum number of pending requests. The default value is 16 and should be adequate for most systems. Setting this value too high might actually reduce throughput.

• CGI Stub Timeout: Causes the server to kill any CGI stub processes that have been idle for the number of seconds set by this directive. Once the number of processes is at the minimum stubs size, it does not kill any more processes. The default is 30.

• CGI Timeout: Limits the maximum time in seconds that CGI processes can run. The default is –1, which means there is no timeout.