I wonder how much of the linux kernel Brendan Gregg has read. I bet it is a decent bit. Also, this guy has posted numerous blogs on the very intimate details of the Linux kernel and even given talks on it. I was lucky enough to watch one of his talks last year @ Monitorama and it was my favorite talk of the entire conference for the level of technical depth it went into.
Whether or not you think he is good based on your dislike for the top doesn't make it any less of a fantastic technical post.
You seem to have got my argument the wrong way round, I wasn't claiming that people who can optimise networking haven't read the kernel source code, and I said nothing to do with the skill or knowledge of Brendan Gregg. I simply dislike such polarising, over the top "everything is black or white" statements.
Whether or not you think he is good based on your dislike for the top doesn't make it any less of a fantastic technical post.
This was the talk I saw, and it was amazing:
https://blog.packagecloud.io/eng/2016/06/29/monitorama-2016-...