Note: Not tested on multithreaded MPM... Feedback is very welcome... Later will be tested on worker mpm
Note: Please always check overload.conf for more recent options

Small module which provides the ability to stop processing apache request if load average is too high.
Can be used inside directory/location to implement custom 503 page.
These options available:
    By default all flag values (ON/OFF) are OFF. All other values are int and not set, if string - some value is set.

#OverloadEnable
Flag - default OFF
Enable or disable mod_overload

#OverloadLoadAvg1min
INT - default not set, ignored if not set
Maximum tolerable 1min load average, after which HTTP 503 is returned

#OverloadLoadAvg5min
INT - default not set, ignored if not set
Maximum tolerable 5min load average, after which HTTP 503 is returned

#OverloadLoadAvg15min
INT - default not set, ignored if not set
Maximum tolerable 15min load average, after which HTTP 503 is returned

#OverloadLogRequests
Flag - default OFF
Log request which were executing when too high load average discovered

#OverloadLowerHasPrecedence
Flag - default OFF
If current 1min load average is less then current 5min load average and 5min load average is higher then OverloadLoadAvg5min allows, then proceed with request. No 503 error returned. The same with 5min load average and 15min load average. Shorter time frame low average has precedence against longer one.

#OverloadAllow503Request
Flag - default OFF
Allow request which have 503 status (subrequest), needed if you want to have custom Error page (define ErrorDocument 503...)

#OverloadKillAllRequests
Flag - default OFF
Not recommended, just kill all current running requests.

#OverloadLogOneAtATime
Flag - default OFF
Module should only log one request listing at a time to avoid congestion

#OverloadLogOneAtATimeLockFile
String - Default value /tmp/mod_overload.lock
Lock file used to implement one log at a time, somewhere where apache can write it...


#OverloadRequestKillSignal 
Int - default value 9
Kill signal used to kill request (useful if you need core dump..., default - 9 (SIGKILL))

#OverloadKillLongRunningRequests
Flag - default OFF
Kill long running request, request time is specified with another key

#OverloadLongRunningRequestTime
INT - default not set, ignored if not set
The request time which is trigger for killing

#OverloadKillLongRunningRequestsAtATime
Flag - default OFF
Only one running request can kill other request, to avoid congestion

#OverloadKillLongRunningRequestsAtATimeLockFile /tmp/mod_overload_kill.lock
String - default value /tmp/mod_overload_kill.lock
Lock file used to implement one kill at a time, somewhere where apache can write it...

Example excluding some from interacting with mod_overload
#<Directory /var/www/error/>
#   OverloadEnable Off
#</Directory>