Copy '/opt/configs/apache/tpl/~lxcenter.conf' to '/opt/configs/apache/tpl/custom.~lxcenter.conf' and then '$keepalive = 'Off';' to '//$keepalive = 'Off';' in ' '/opt/configs/apache/tpl/custom.~lxcenter.conf'. After that, go to 'webserver configure' and select 'medium'' or 'high' for 'apache optimize'.