Evaluating JSON.parse vs object literal. cf. https://v8.dev/blog/cost-of-javascript-2019

json-bench.js

const fs = require("fs");
const assert = require("assert");
const jsonBuffer = fs.readFileSync("./schema.json");

const object = JSON.parse(jsonBuffer.toString());
const jsonParseExpr = `(JSON.parse(${JSON.stringify(JSON.stringify(object))}))`;
const objectLiteralExpr = `(${JSON.stringify(object)})`;

const N = 100;

console.log(`json source lengt: ${jsonParseExpr.length}`);
console.log(`objlit      length: ${objectLiteralExpr.length}`);
console.log("");
console.log(`N = ${N}`);
console.log("");

console.time("json source");
for (let i = 0; i < N; i++) {
  const o = eval(jsonParseExpr);
  assert(typeof o === "object");
}
console.timeEnd("json source");

console.time("object literal");
for (let i = 0; i < N; i++) {
  const o = eval(objectLiteralExpr);
  assert(typeof o === "object");
}
console.timeEnd("object literal");