How to check identical array in most efficient way? [duplicate]

So, what’s wrong with checking each element iteratively?

function arraysEqual(arr1, arr2) {
    if(arr1.length !== arr2.length)
        return false;
    for(var i = arr1.length; i--;) {
        if(arr1[i] !== arr2[i])
            return false;
    }

    return true;
}