I recently discovered a few major problems on my end, that led to major CPU spikes. Worst part... I was having a hell of a time finding the accounts that were throwing them over their limits.
1) I stumbled upon this amazing little cPanel script (no clue how it took me until last week to find it):
https://ssp.cpanel.net/ssp
2) I found that I had EA4-experimental versions of memcached & memcache installed. Removing those fixed my CPU overages. Server runs like BUTTAH now!