File mod_overload.conf of Package apache2-mod_overload

# Small module which provides the ability to stop processing apache request if load average is too high.
# Can be used inside virtual host or <Directory>, <Location>.
# You can implement some custom 503 error, by pointing ErrorDocument to directory/location 
# which has mod_overload disabled or with higher overload value, where you can add some custom page/error handling...
# This options available:
#    By default all flag values (ON/OFF) are OFF. All other values are integer, if you do not set integer value, then this parameter is ignored

#OverloadEnable On
# Enable or disable mod_overload

#OverloadLoadAvg1min 100
# Maximum tolerable 1min load average, after which HTTP 503 is returned

#OverloadLoadAvg5min 60
# Maximum tolerable 5min load average, after which HTTP 503 is returned

#OverloadLoadAvg15min 60
# Maximum tolerable 15min load average, after which HTTP 503 is returned

#OverloadLogRequests On
# Log request which were executing when too high load average discovered

#OverloadLowerHasPrecedence On
# 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 Off
#Allow request which have 503 status (subrequest), needed if you want to have custom Error page (define ErrorDocument 503...)

#OverloadKillAllRequests Off
# Not recommended, just kill all current running requests.
</IfModule>