I love cool terminal apps for Linux. I know Terminal is “old school” and all, but seriously, these apps are pretty awesome, and the people who come up with them do some amazing work.
I feel like a Pro when I open up a terminal, then break it into several windows, and get some diagnostics running all over the screen.
https://www.tecmint.com/mytop-mysql-mariadb-database-performance-monitoring-in-linux/