JS Parallel Processing using bun

parallel_test.ts

// Refrence from    https://stackoverflow.com/a/42114595

// Tested on Bun v1.1.21 - https://bun.sh 
// date: 10-08-2024

// console.clear();

// Testing
const TOTAL_TASKS = 5;
// const TOTAL_TASKS = 10;
// const TOTAL_TASKS = 100;
// const TOTAL_TASKS = 1000;
// const TOTAL_TASKS = 10000;

const TASK_DELAY = 500; // in ms

const wait: Function = (ms: number, data: any): any => {
    return new Promise(resolve => setTimeout(resolve.bind(self, data), ms));
}

/** 
 * These will be run in series, because we call
 * a function and immediately wait for each result, 
 * so this will finish in (TOTAL_TASKS * TASK_DELAY).
 */
async function series(): Promise<any> {
    let results: Array<any> = [];
    for (let idx = 1; idx <= TOTAL_TASKS; idx++) {
        const taskResult = await wait(TASK_DELAY, `s-task_${idx}`);
        results.push(taskResult);
    }

    return results;
}

/** 
 * While here we call the functions first,
 * then wait for the result later, so 
 * this will finish in around TASK_DELAY ms.
 */
async function parallel(): Promise<any> {
    let tasks: Array<Function> = [];
    for (let idx = 1; idx <= TOTAL_TASKS; idx++) {
        tasks.push(wait(TASK_DELAY, `p-task_${idx}`));
    }

    return await Promise.all(tasks);
}

async function taskRunner(fn: Function, label: string) {
    const startTime = performance.now();
    console.log(`${TOTAL_TASKS} ${label} tasks starting...`);
    let result = await fn();

    console.log(`${TOTAL_TASKS} ${label} tasks finished in ${(performance.now() - startTime)} ms with following result:`);
    console.log(result);
    console.log("");
}

void taskRunner(series, 'series');
void taskRunner(parallel, 'parallel');
console.log("");