使用减法进行快照比较

🌐 Snapshot diffing with subtract

const { createHistogram } = require('node:perf_hooks');

const total = createHistogram();
const snapshot = createHistogram();

// Record values into total...
// Periodically snapshot for "last interval" analysis:
snapshot.add(total);

// Later, take a new snapshot and diff:
const newSnapshot = createHistogram();
newSnapshot.add(total);
newSnapshot.subtract(snapshot);
// newSnapshot now contains only the values recorded since the last snapshot
console.log('Recent p99:', newSnapshot.percentile(99)); 拷贝