performancelisted

# Performance The budget is **8 ms a frame** for everything. Almost nothing in this kit costs a measurable fraction of that; when a Lattice game is slow it is almost always one of about six specific things, and this skill is those six in the order they are worth checking. **Measure before you change anything.** Half the optimizations people reach for here are unavailable — there is no sprite cache to add, it was measured and deleted — and the other half are in the wrong place. --- ## First: is the number you are reading true? Two instruments, and the one that reads better is blind. ```ts import type { Loop } from '@latticekit/loop'; export function verdict(loop: Loop): string { const gap = loop.stats.worstGapMs; // wall time between two PAINTED frames const cadence = loop.stats.cadenceMs; // the display's own period, as observed // The verdict is the RATIO. Under about 1.5 cadences dropped no frames. return `${gap.toFixed(1)} ms worst against a ${cadence.toFixed(1)} ms display`; } ``` **`loop.stats.worstFrameMs` is the pump's own wall time** — the loop reads the clock on the way into a pump and on the way out. **A garbage collection, a style recalculation, or anything else that lands *between* two pumps is in neither reading.** That is not hypothetical: - one game measured **23.1 ms worst on one machine and 13.1 ms on another for the same build**, because whether the pause lands inside a pump is machine-dependent and the readout is not; - another shi