Scalyr [1] can do this. (Disclaimer: I am the founder of Scalyr, and it's a commercial product.) We aim to be a one-stop-shopping monitoring tool: collect everything you might want to collect, and let you analyze it in any way you want. To your question, we can collect CPU, memory, I/O, and other stats for specified processes [2], and give you graphs, rolled-up dashboards, and alerts on that data.

We're always looking for feedback, and we're happy to give out discounted or free accounts to startups. Drop me a line -- steve@[company domain] -- if you're interested.

[1]: https://www.scalyr.com [2]: https://www.scalyr.com/appDashboard