To stop the tomcat for making a big catalina.out file, use logrotate to rotate the logfiles as needed
For most Linux distro's:
/etc/logrotate.d/confluence
/pack/confluence/logs/catalina.out {
daily
rotate 7
compress
copytruncate
delaycompress
missingok
size 10M
notifempty
}
This rotates the logfile dailay, and keep 7 copies. Refer to http://linuxcommand.org/man_pages/logrotate8.html