In many scenarios, we face trouble to stop AEM/CQ5 instances, even after stopping the service, the java instance keeps on running. The best way to stop an AEM instance is through the following command
[priv_user@some-server home_directory]# pid=`fuser -k -TERM 450{2,3}/tcp` && cd /mnt/crx/*/crx-quickstart && time tail -n0 -f --pid $pid logs/error.log && mv -v logs/error.log{,.`date +%F+%R`} && find launchpad/felix -name digraph -ls -delete