How do i compare PHP Efficiency between two algorithm?

Here is two function that creates 1000 files inside 1000 folders in two different fashion:

First Method

function createEverything() {
    for($i = 1; $i == 1000; $i++) {
        mkdir('test/'.$i);
        file_put_contents("test/".$i."/".$i.".txt", time());
    }
}

Second Method

function createEverything() {
    for($i = 1; $i == 1000; $i++) {
        exec("mkdir test/".$i);
        exec("touch test/".$i."/".$i.".txt");
        exec("echo ".time()." >> test/".$i."/".$i.".txt");
    }
}

The second method utilized the unix commands in order to create 1000 files inside 1000 folders.

Now my question is how i can get the CPU information's, RAM uses and other performance related informations separately for this two separate method, so i can compare which one is appropriate for me?