I did a whole stack of servers using SNMP based monitoring years ago and it was amazing. I could see loads, memory stats, NIC utilisation, disk space, and all sorts of other things. I tried Cacti and Icinga and settled on the latter but they are all fairly similar. Once you are generating the data you van do whatever you like with it, so monitoring load attributable to which actual executable is definitely manageable. It is also handy for getting notifications for something being down, losing stability, or just being out if whack.