Direct answer
Large explosions generate entity movement, block destruction, drops and updates; TNT limits control a different part of the process than pure rendering.
How to check it
- Profile a representative TNT cannon or minigame blast with players at a safe distance and monitor tick spikes.
- Compare block-destroying blasts against a no-block-damage test on an expendable world.
- Read the actual
max-tnt-per-tickand explosion optimization options supported by your server version.
Example: A hundred isolated blasts spread across a minute differ from a hundred TNT entities exploding in one tick. Compare the worst-tick cost and intended cannon timing.
What to change
Prevent unintended simultaneous detonations, cap automated launch frequency in minigames or stagger planned show effects. Adjust optional explosion optimization only after testing mechanics.
Software and version notes
Paper optimize-explosions and Spigot TNT limits are not interchangeable. Very low limits can disrupt TNT movement and timing-critical contraptions; never experiment on live technical builds.
Verify the result
Confirm damage, redstone machines and arena resets work with fewer peak tick stalls.