Parallel Programming

Parallel programming is a technique used to utilize multiple processors or cores in order to achieve faster execution of programs. With the advent of multi-core processors, parallel programming has become increasingly important in improving performance and efficiency.

In parallel programming, tasks are divided into smaller subtasks that can be executed simultaneously on different processors or cores. This allows for better utilization of hardware resources and can result in significant speedup compared to sequential execution.

One common analogy used to explain parallel programming is a basketball team. In a basketball game, the team works together to achieve a common goal of scoring points and winning the game. Each player on the team performs their own tasks, such as shooting, passing, and defending, simultaneously. Similarly, in parallel programming, multiple tasks are performed concurrently by different processors or cores.

Let's take a look at an example of parallel programming in JavaScript:

1// Define an array of numbers
2const numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
3
4// Define a function to calculate the square of a number
5function calculateSquare(number) {
6  return number * number;
7}
8
9// Create a parallel map function using the map() method and multiple threads
10function parallelMap(array, callback) {
11  const promiseArray = array.map((element) => {
12    // Create a promise for each element
13    return new Promise((resolve) => {
14      // Execute the callback function for the element
15      const result = callback(element);
16      // Resolve the promise with the result
17      resolve(result);
18    });
19  });
20
21  // Return a new promise that resolves when all promises are resolved
22  return Promise.all(promiseArray);
23}
24
25// Use the parallel map function to calculate the squares of numbers
26parallelMap(numbers, calculateSquare)
27  .then((result) => {
28    console.log('Squared numbers:', result);
29  });