A benchmark of reflection API performance in PHP

reflection-bench.php

<?php

/**
 * Benchmark: Reflection Performance
 *
 * Conclusion: there is no performance-gain from caching reflection-objects.
 */

define('NUM_TESTS', 10);

header('Content-type: text/plain');

$func = function($a, $b, $c) {
  // ...
};

class Foo
{
  public $a;
  protected $b;
  private $c;
  
  public function foo($a,$b,$c) {}
  protected function bar($a,$b,$c) {}
  private function baz($a,$b,$c) {}
}

for ($i=0; $i<NUM_TESTS; $i++) {
  $start = microtime(true);
  $ref = new ReflectionClass($func);
  $end = microtime(true);
  
  echo "ReflectionClass # $i: " . number_format(1000000*($end-$start), 3) . " µsec\n";
}

for ($i=0; $i<NUM_TESTS; $i++) {
  $start = microtime(true);
  $ref = new ReflectionFunction($func);
  $end = microtime(true);
  
  echo "ReflectionFunction # $i: " . number_format(1000000*($end-$start), 3) . " µsec\n";
}

class Cache
{
  private $cache = array();
  
  public function getReflection($class)
  {
    if (!isset($this->cache[$class])) {
      $this->cache[$class] = new ReflectionClass($class);
    }
    return $this->cache[$class];
  }
}

$cache = new Cache;

for ($i=0; $i<NUM_TESTS; $i++) {
  $start = microtime(true);
  $ref = $cache->getReflection('Foo');
  $end = microtime(true);
  
  echo "Cached ReflectionClass # $i: " . number_format(1000000*($end-$start), 3) . " µsec\n";
}

Is that saying that Reflection almost does not affect the performance on PHP 8.1 and 7.2 ?

Is that saying that Reflection almost does not affect the performance on PHP 8.1 and 7.2 ?

I think it has a very minimal impact, so unless you're in a performance-critical scenario, I don't think you need to worry about reflections negatively affecting your application.

PHP 8.2.10:

ReflectionClass # 0: 1.907 µsec
ReflectionClass # 1: 0.954 µsec
ReflectionClass # 2: 0.000 µsec
ReflectionClass # 3: 0.000 µsec
ReflectionClass # 4: 0.000 µsec
ReflectionClass # 5: 0.000 µsec
ReflectionClass # 6: 0.000 µsec
ReflectionClass # 7: 0.000 µsec
ReflectionClass # 8: 0.000 µsec
ReflectionClass # 9: 0.000 µsec
ReflectionFunction # 0: 0.000 µsec
ReflectionFunction # 1: 0.000 µsec
ReflectionFunction # 2: 0.000 µsec
ReflectionFunction # 3: 0.000 µsec
ReflectionFunction # 4: 0.000 µsec
ReflectionFunction # 5: 0.000 µsec
ReflectionFunction # 6: 0.000 µsec
ReflectionFunction # 7: 0.000 µsec
ReflectionFunction # 8: 0.000 µsec
ReflectionFunction # 9: 0.000 µsec
Cached ReflectionClass # 0: 2.861 µsec
Cached ReflectionClass # 1: 0.000 µsec
Cached ReflectionClass # 2: 0.000 µsec
Cached ReflectionClass # 3: 0.000 µsec
Cached ReflectionClass # 4: 0.000 µsec
Cached ReflectionClass # 5: 0.000 µsec
Cached ReflectionClass # 6: 0.000 µsec
Cached ReflectionClass # 7: 0.000 µsec
Cached ReflectionClass # 8: 0.000 µsec
Cached ReflectionClass # 9: 0.000 µsec

PHP 8.2.10 (cli) (built: Sep  2 2023 06:59:22) (NTS)
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