Script to benchmark the performance of adding array elements (配列要素追加処理のベンチマークスクリプト)

benchmarkAddArrayEelements.php

<?php

function benchmark(string $name, Closure $callback)
{
    $start = microtime(true);
    $callback();
    $time = microtime(true) - $start;
    echo sprintf(
        "%24s =>\tTime: %.6f sec.\n",
        $name,
        $time
    );
}

$iteration = 10000;

// array_push()
benchmark(
    'array_push()',
    function () use ($iteration) {
        $a = [];
        for ($i = 0; $i < $iteration; $i++) {
            array_push($a, 1);
        }
    }
);

// square brackets
benchmark(
    'square brackets []',
    function () use ($iteration) {
        $a = [];
        for ($i = 0; $i < $iteration; $i++) {
            $a[] = 1;
        }
    }
);

// union operator
benchmark(
    'union operator +=',
    function () use ($iteration) {
        $a = [];
        for ($i = 0; $i < $iteration; $i++) {
            $a += [count($a) => 1];
        }
    }
);

// array_merge()
benchmark(
    'array_merge()',
    function () use ($iteration) {
        $a = [];
        for ($i = 0; $i < $iteration; $i++) {
            $a = array_merge($a, [1]);
        }
    }
);

// unpacking operator
benchmark(
    'unpacking operator [...]',
    function () use ($iteration) {
        $a = [];
        for ($i = 0; $i < $iteration; $i++) {
            $a = [...$a, 1];
        }
    }
);

// ArrayObject
benchmark(
    'ArrayObject',
    function () use ($iteration) {
        $a = new ArrayObject([]);
        for ($i = 0; $i < $iteration; $i++) {
            $a->append(1);
        }
    }
);

Result of running 5 times:

• 1st:

              array_push() =>	Time: 0.004728 sec.
        square brackets [] =>	Time: 0.002071 sec.
        union operator += =>	Time: 0.003370 sec.
            array_merge() =>	Time: 0.105991 sec.
  unpacking operator [...] =>	Time: 0.311016 sec.
              ArrayObject =>	Time: 0.006851 sec.
  

• 2nd:

              array_push() =>	Time: 0.004765 sec.
        square brackets [] =>	Time: 0.002110 sec.
        union operator += =>	Time: 0.003569 sec.
            array_merge() =>	Time: 0.107618 sec.
  unpacking operator [...] =>	Time: 0.330064 sec.
              ArrayObject =>	Time: 0.004905 sec.
  

• 3rd:

              array_push() =>	Time: 0.004920 sec.
        square brackets [] =>	Time: 0.002054 sec.
        union operator += =>	Time: 0.003514 sec.
            array_merge() =>	Time: 0.113861 sec.
  unpacking operator [...] =>	Time: 0.300871 sec.
              ArrayObject =>	Time: 0.004863 sec.
  

• 4th:

              array_push() =>	Time: 0.005846 sec.
        square brackets [] =>	Time: 0.002054 sec.
        union operator += =>	Time: 0.003339 sec.
            array_merge() =>	Time: 0.106517 sec.
  unpacking operator [...] =>	Time: 0.360666 sec.
              ArrayObject =>	Time: 0.005932 sec.
  

• 5th:

              array_push() =>	Time: 0.005791 sec.
        square brackets [] =>	Time: 0.002138 sec.
        union operator += =>	Time: 0.004024 sec.
            array_merge() =>	Time: 0.118922 sec.
  unpacking operator [...] =>	Time: 0.393219 sec.
              ArrayObject =>	Time: 0.005309 sec.