[from the original at: http://www.brendangregg.com/blog/2016-01-27/unikernel-profiling-from-dom0.html]
Is a unikernel an impenetrable black box, resistant to profilers, tracers, fire, and poison? At SCaLE14x this weekend there was a full day track on unikernels, after which I was asked about unikernel profiling and tracing. I'm not an expert on the topic, and wasn't able to answer these questions at the time, however, I've since taken a quick look using MirageOS and Xen.
In this post I'll share a proof of concept for profiling a Xen domU unikernel from dom0. I didn't find any recent examples of doing this (there are some 2006 oprofile patches). This is just a PoC, not yet a polished product. Although, by the time you read this, there may be something better based on this work (check comments).