Linux is technically a Kernel, but “knowing linux” involves far more.
Some books about the internals of Linux:
- Linux Kernel Development by Robert Love
- The Linux Programming Interface by Michael Kerrisk
Observability and Performance
- Systems Performance: Enterprise and the Cloud by Brendan Gregg
- “2nd Ed will be released Dec 9, 2020”
- BPF Performance Tools by Brendan Gregg