As other replies say, I too have read that the Lions' stuff is highly recommended; have not read it though. I have read good chunks of The Design of the Unix Op

As other replies say, I too have read that the Lions' stuff is highly recommended; have not read it though. I have read good chunks of The Design of the Unix Operating System by Maurice Bach, some years ago, which included both concepts and either code or pseudocode for various kernel algorithms such as scheduling, etc, IIRC. Might not be up to date for today's Unixen, but should be good for learning a lot about the basics of Unix internals, I'd say. Disclaimer: I read it out of interest, not done kernel level work myself. Edited for typo.