PHP教學-抓取記憶體用量( linux )

<?php
function echo_memory_usage() {
    $mem_usage = memory_get_usage(true);

    if ($mem_usage < 1024)
        echo $mem_usage." bytes";
    elseif ($mem_usage < 1048576)
        echo round($mem_usage/1024,2)." kilobytes";
    else
        echo round($mem_usage/1048576,2)." megabytes";

    echo "<br/>";
}
echo echo_memory_usage();

function get_server_memory_usage(){

    $free = shell_exec('free');
    $free = (string)trim($free);
    $free_arr = explode("\n", $free);
    $mem = explode(" ", $free_arr[1]);
    $mem = array_filter($mem);
    $mem = array_merge($mem);
    $memory_usage = $mem[2]/$mem[1]*100;

    return $memory_usage;
}

echo get_server_memory_usage();