PHP Utilisation de la mémoire

Parfois, il est bon de savoir ou même très important de savoir, combien votre script PHP utilise la mémoire.

Ce n'est qu'un exemple simple d'une classe, qui peut être utilisé pour collecter les informations d'utilisation de la mémoire de script PHP et d'imprimer toutes les informations.

Il est facile de reformater la sortie, si vous voulez l'utiliser par exemple sur la page web  d'un script de ligne de commande.

Ou même faire une autre fonction pour les pages Web et un autre pour les scripts en ligne de commande.

<?php
 
  class MemoryUsageInformation {
    private $real_usage;
    private $statistics = array();
 
    // Memory Usage Information constructor
    public function __construct($real_usage = false) {
      $this->real_usage = $real_usage;
    }
 
    // Returns current memory usage with or without styling
    public function getCurrentMemoryUsage($with_style = true) {
      $mem = memory_get_usage($this->real_usage);
      return ($with_style) ? $this->byteFormat($mem) : $mem;
    }
 
    // Returns peak of memory usage
    public function getPeakMemoryUsage($with_style = true) {
      $mem = memory_get_peak_usage($this->real_usage);
      return ($with_style) ? $this->byteFormat($mem) : $mem;
    }
 
    // Set memory usage with info
    public function setMemoryUsage($info = '') {
      $this->statistics[] = array('time' => time(),
                                  'info' => $info,
                                  'memory_usage' => $this->getCurrentMemoryUsage());
    }
 
    // Print all memory usage info and memory limit and
    public function printMemoryUsageInformation() {
      foreach ($this->statistics as $satistic) {
        echo  "Time: " . $satistic['time'] .
              " | Memory Usage: " . $satistic['memory_usage'] .
              " | Info: " . $satistic['info'];
        echo "n";
      }
      echo "nn";
      echo "Peak of memory usage: " . $this->getPeakMemoryUsage();
      echo "nn";
    }
 
    // Set start with default info or some custom info
    public function setStart($info = 'Initial Memory Usage') {
      $this->setMemoryUsage($info);
    }
 
    // Set end with default info or some custom info
    public function setEnd($info = 'Memory Usage at the End') {
      $this->setMemoryUsage($info);
    }
 
    // Byte formatting
    private function byteFormat($bytes, $unit = "", $decimals = 2) {
    $units = array('B' => 0, 'KB' => 1, 'MB' => 2, 'GB' => 3, 'TB' => 4,
    'PB' => 5, 'EB' => 6, 'ZB' => 7, 'YB' => 8);
    
    $value = 0;
    if ($bytes > 0) {
    // Generate automatic prefix by bytes
    // If wrong prefix given
    if (!array_key_exists($unit, $units)) {
    $pow = floor(log($bytes)/log(1024));
    $unit = array_search($pow, $units);
    }
    
    // Calculate byte value by prefix
    $value = ($bytes/pow(1024,floor($units[$unit])));
    }
    
    // If decimals is not numeric or decimals is less than 0
    // then set default value
    if (!is_numeric($decimals) || $decimals < 0) {
    $decimals = 2;
    }
    
    // Format output
    return sprintf('%.' . $decimals . 'f '.$unit, $value);
    }
  }
 
?>

Exemple d'utilisation de la mémoire

<?php
 
  // Create new MemoryUsageInformation class
  $m = new MemoryUsageInformation(true);
 
  // Set start
  $m->setStart();
 
  // Create example array
  $a = array();
 
  // Set memory usage before loop
  $m->setMemoryUsage('Before Loop');
 
  // Fill array with
  for($i = 0; $i < 100000; $i++) {
    $a[$i] = uniqid();
  }
 
  // Set memory usage after loop
  $m->setMemoryUsage('After Loop');
 
  // Unset array
  unset($a);
 
  // Set memory usage after unset
  $m->setMemoryUsage('After Unset');
 
  // Set end
  $m->setEnd();
 
  // Print memory usage statistics
  $m->printMemoryUsageInformation();

Exemple de résultat d'utilisation de la mémoire

Time: 1321095944 | Memory Usage: 768.00 KB | Info: Initial Memory Usage
Time: 1321095944 | Memory Usage: 768.00 KB | Info: Before Loop
Time: 1321095951 | Memory Usage: 24.25 MB | Info: After Loop
Time: 1321095951 | Memory Usage: 1.25 MB | Info: After Unset
Time: 1321095951 | Memory Usage: 1.25 MB | Info: Memory Usage at the End
 
Peak of memory usage: 24.25 MB