Why does my application timeout on Apache?
There are several reasons why a timeout occurs and both GAS and Web server logs might need to be investigated.
The Apache module mod_reqtimeout controls the request data rate. If the reception of the data is considered too slow, Apache can close an HTTP connection before other configured timeouts have expired.
When a response is written to an HTTP request where Apache has closed the socket, you may get a "SYSTEM ERROR" logged in the dispatcher log. As this is a system error, the message outputted may vary from system to system.
It may also happen that the dispatcher can respond correctly, but that the Web server is unable to forward the answer. In this case, there is no error in the GAS so you must check the Web server logs.
Starting with GAS version 3.00, the mod_reqtimeout module is no longer loaded by the GAS configuration for Apache 2.4.
For more information on working with the Apache timeout, see the "Apache Module mod_reqtimeout" page in the Apache documentation.