cache

Identical replicas serving identical traffic should produce identical numbers, so a difference is a defect and the fleet median is the tool that finds it. Five causes, the three that are about the replica and the two that are about what it was sent.

The tiling is ten lines and the theory is a working-set calculation. The interesting part is that the obvious benchmark does not measure what it appears to, because the library underneath is already tiled, and knowing which effect your numbers contain is the skill being tested.