Like all good developers, I do not know everything and will happily admit this. I've spent some time recently reading a couple of books to help fill in some gaps in my knowledge.
I've complained previously about disliking benchmarking. More generally, I'm not really a fan of performance analysis. I always feel like I get stuck at coming up with an approach to "it's going slower, why" beyond the basics. I watched a video of Brendan Gregg's talk from kernel recipes, and ended up going down the black hole1 of reading his well written blog. He does a fantastic job of explaining performance analysis concepts as well as the practical tools to do the analysis. He wrote a book several years ago and I happily ordered it. The book explains how to apply the USE method to performance problems across the system. This was helpful to me because it provides a way to generate a list of things to check and how to check them. It addresses the "stuck" feeling I get when dealing with performance problems. The book also provides a good high level overview of operating systems concepts. I'm always looking for references for people who are interested in kernels but don't know where to start and I think this book could fill a certain niche. Even if this book has been out for several years now, I was very excited to discover it.
I consider networking the biggest black hole of mystery in the kernel. I've never been a network or sysadmin for anything except my own Linux machines. Most of my networking debugging involves just googling for the correct command to type. I ended up buying a copy of Volume I of TCP/IP Illustrated. This is the canonical text and it's quite dense. For my style though, it's been helpful for grasping concepts. I have a better idea of exactly how packets flow and what exactly various networking functions (e.g. VPN) actually do. It's not very useful for practical experience though so I want to find some tasks to apply some of the skills I've learned. Maybe I'll write more if I find something interesting.
I suffer from https://xkcd.com/214/ syndrome for all internet content. ↩