Monitoring File Changes in PHP

benchmark

stat
avg: 0.216100677729
min: 0.167356967926
max: 0.367993116379

sha1_file
avg: 0.456373734236
min: 0.385113954544
max: 0.842865943909

filemtime
avg: 0.210854323149
min: 0.177852153778
max: 0.37334394455

benchmark.php

<?php

/**
 * Benchmarks the running time of the supplied closure and outputs its average,
 * min and max over the given number of iterations.
 *
 * @param string   $title      Title of the benchmark to print
 * @param int      $iterations Number of times to run the anonymous function
 * @param callable $callable   The function to measure
 */
function benchmark($title, $iterations, $callable)
{
    $runningTimes = [];

    for ($i = 0; $i < $iterations; $i++) {
        $startTime = microtime(true);

        $callable();

        $endTime = microtime(true);
        $time = $endTime - $startTime;
        $runningTimes[] = $time;
    }

    $avg = array_sum($runningTimes) / count($runningTimes);
    $min = min($runningTimes);
    $max = max($runningTimes);

    echo "\n$title\navg: $avg\nmin: $min\nmax: $max\n";
}

/**
 * If the given path is a file, the function is called with the path as its
 * argument. Otherwise, if the path is a directory, this function recurses over
 * all sub-folders, invoking the $callable for each file.
 *
 * @param string   $path     A valid path to a file or directory
 * @param callable $callable The function to invoke for each file found, with
 *                           its path as the argument
 */
function recurseCall($path, $callable)
{
    if (is_file($path)) {
        $callable($path);
        return;
    }

    $path = realpath($path);
    $dirIterator = new RecursiveDirectoryIterator($path);
    $iterator = new RecursiveIteratorIterator($dirIterator);

    $files = new RegexIterator($iterator, '/^.+\.php$/i',
        RecursiveRegexIterator::GET_MATCH);

    foreach ($files as $file) {
        $filePath = $file[0];

        if (is_file($filePath)) {
            $callable($filePath);
        }
    }
}

$directory = dirname(__FILE__) . '/Symfony';

// Using stat size and mtime
benchmark('stat', 1000, function() use ($directory) {
    clearstatcache();
    recurseCall($directory, function($path) {
        $stat = stat($path);
        // $stat['mtime'], $stat['size'];
    });
});

// Using sha1_file
benchmark('sha1_file', 1000, function() use ($directory) {
    recurseCall($directory, function($path) {
        $digest = sha1_file($path);
    });
});

// Using filemtime
benchmark('filemtime', 1000, function() use ($directory) {
    recurseCall($directory, function($path) {
        $time = filemtime($path);
    });
});