W3C httpd manual

Timeout Settings

Something may go wrong with the connection to the client causing httpd to hang infinitely doing nothing. This can be avoided by setting timeouts on different tasks that the server performs. All of these timeouts have relatively good default values by default and they don't usually need to be changed.

All the times for these directives are of form:

        45 secs
        10 mins
        2 mins 30 secs
        1 hour

InputTimeOut

InputTimeOut diretictive specifies the time to wait for the client to send the request (the MIME-header part of it, not the message body). Default value is:
        InputTimeOut  2 mins

OutputTimeOut

OutputTimeOut diretictive specifies the time to allow for sending the response. Default value is:
        OutputTimeOut  20 mins
If you are serving huge files for clients behind slow connections you may want to increase this value if you hear of connections being cut in the middle of transfer.


ScriptTimeOut

ScriptTimeOut diretictive specifies the time to allow for server scripts to finish. If a script doesn't return in the time specified httpd will send TERM and KILL signals to it (with 5 seconds in between to let scripts do cleanup upon exit). Default value is:
        ScriptTimeOut  5 mins


httpd@w3.org, July 1995