For Array, is it more efficient to use map() & reduce() instead of forEach() in javascript?

Question

1)As we know, there\'s no side-effect with map() and reduce(). Nowadays, we also have muti-core on cell phone. So is it more efficient to use them?

2)On the other h

Answer 1

As long as the dimensions of the array are very low ( in order of 10's) then there is not much a difference in the performance, but when the size of the array increases to a very large value, then using conventional for loop is a great and better method, because we just need to loop through the elements and get a value at a specific index as we point, but in other methods, not only we are getting the value at an index, but also additional information such as the index, (in map, reduce, forEach) and accumulator value (in reduce). And these methods as need an a callback function, they both take up a great deal of stock on the memory for callbacks which further reduces the performance speed.

You can check the justification of this with the following script. Just see the values that are console logged.

 var scripts=[];
// GLOBAL variales declaration
var a=[];
function preload() {
    for(var i=0;i<100000;i++) a[i]=i;
}
preload();
// TEST function 0
scripts.push(function() {
    var sum=0;
    a.forEach(function(v) {
        sum+=v;
    });
    //console.log(sum);
});
// TEST function 1
scripts.push(function() {
    a.reduce(function(acc,v) {
        return acc+v;
    });
});
// TEST function 2
scripts.push(function() {
    var sum=0;
    for(var i=0;i