MySQL’s SHOW STATUS and SHOW VARIABLES commands (or queries against the corresponding INFORMATION_SCHEMA tables) don’t always show what they say. In particular, SHOW STATUS contains several rows that aren’t status-related, but are really configuration variables in my opinion (and it is an opinion — sometimes the difference isn’t black and white).
Here’s a short list of some status counters that I think are really better off as configuration variables:
Most of those are legacy, but Slave_heartbeat_period is a recent addition.
Can you think of others? What are your favorite oddities of SHOW STATUS and SHOW VARIABLES?