Apache on Plesk

Optimizations

In Plesk, Apache optimizations are set in:
/etc/httpd/conf.d/

You'll want to change the settings in the appropriate file for the MPM:

mpm_prefork.conf
mpm_event.conf

(Might be httpd.conf on older Plesk versions)

Domlog diving

find /var/www/vhosts/*/logs/ ! -path /var/www/vhosts/system -name access_log | while read LOG; do echo -e "`echo $LOG|awk -F'/' '{print $5}'`: `wc -l $LOG|awk '{print $1}'`";  done |sort -rnk2 |head -25