Quick bench of a loop that does an async/await call on every iteration

async-bench.js

"use strict";

class Bench {
    constructor() {
        this.x = 0;
        this.iters = 1000000;
    }

    ms() {
        return Date.now();
    }

    stepSync() {
        return this.x = Math.random();
    }

    async stepAsync() {
        return this.x = Math.random();
    }

    runSync() {
        let start = this.ms();
        for (let i = 0; i < this.iters; i++) {
            this.stepSync();
        }
        let delta = this.ms() - start;
        return delta;
    }

    async runAsync() {
        let start = this.ms();
        for (let i = 0; i < this.iters; i++) {
            await this.stepAsync();
        }
        let delta = this.ms() - start;
        return delta;
    }

    async run() {
        console.log('warming up');

        // warmup
        this.runSync();
        await this.runAsync();

        let deltaSync = this.runSync();
        console.log('sync ran in ' + deltaSync + ' ms')
    
        let deltaAsync = await this.runAsync();
        console.log('async ran in ' + deltaAsync + ' ms')
    }
}

let bench = new Bench();
bench.run();

results.txt

$ node async-bench.js 
warming up
sync ran in 25 ms
async ran in 539 ms