Beginner optimization questions

After spending the last few months exploring JUCE, dsp, synth making and thoroughly enjoying myself, I realized that I've got to get real...I don't really know how much CPU usage my synth is using, nor do I know how to track it down. Obviously, once I know my problems, I can take steps to deal with them, but I have to know what the issues are first. 

So...

What's the best way to get an idea of how much CPU my plugin is using? Or is that even the proper question?

If it were a *normal* non-audio app, I could use Instruments and find out all kinds of stuff, but I don't know the best way to do that with an audio plugin. 

One thing that triggered this topic is, I've recently started getting random loud pops every once in a while. Not very often and not all the time. I can't trace the pops to any one thing I've added recently or any specific UI interaction, however, it made me wonder about CPU usage and just how clueless I am right now. Who knows...maybe it's just El Capitan.

Which also makes me wonder about the difference of JUCE in debug mode vs JUCE in optimized mode. 

I realize this is a wandering question, but I think you pros will know what I'm talking about. ANY tips would be greatly appreciated. 

Thank you.

PS - I hope no one minds, but I'm going to cross post this in the Audio Plugins forum as well.