<?php

const EXECUTION_TIME = 60;

// <preparation>
$items = range(0, 10);
// </preparation>

$timingStart = microtime(true);
$memoryStart = memory_get_usage(true);
$peakStart   = memory_get_peak_usage(true);

for ($iterations = 0; $iterations < PHP_INT_MAX; $iterations++) {
    // <code>
    $even = [];
    foreach ($items as $item) {
        if ($item % 2 === 0) {
            $even[] = $item;
        }
    }
    // </code>
    // Timing control:
    if ($iterations % 1000 === 0 &&
        microtime(true) - $timingStart >= EXECUTION_TIME) {
        break;
    }
}

$timingDuration = microtime(true) - $timingStart;
$memoryEnd      = memory_get_usage(true);
$memoryUsage    = $memoryEnd - $memoryStart;
$peakEnd        = memory_get_peak_usage(true);
$peakUsage      = $peakEnd - $peakStart;

echo "\n\n";

printf("Cycles count   : %.2f\n", $iterations);
printf("Cycles by min. : %.2f\n", 60 / $timingDuration * $iterations);
printf("Total time     : %.2f sec.\n", $timingDuration);
printf("Memory usage   : %.2f MB (on end) - %.2f MB (on start) = %.2f MB (delta)\n",
    $memoryEnd / 1048576,
    $memoryStart / 1048576,
    $memoryUsage / 1048576);
printf("Memory peak    : %.2f MB (on end) - %.2f MB (on start) = %.2f MB (delta)\n\n\n",
    $peakEnd / 1048576,
    $peakStart / 1048576,
    $peakUsage / 1048576);