Benchmarking PHP code

Have you ever asked yourself, “I wonder which of these blocks of code will run
faster?” I know I have and I use a very basic template for setting up these
benchmarking experiments. The gist of the script is to run through each block
of code n times tracking the amount of time and memory it took to run. It’s
not nearly as complete as it could be, but it serves as a good enough starting
point for doing some quick tests.

<?php

$n = 1000000

$start_time = microtime(true
$start_mem  = memory_get_usage(true

for ($i = 0 $i < $n $i++)
{

}

$time = microtime(true) - $start_time
$mem  = memory_get_usage(true) - $start_mem

echo "Test 1t{$time}t{$mem}n"

You can duplicate the test block as many times as you need it. Here’s a working
benchmark I wrote to see if PHP’s built-in array_keys function was actually
faster than doing a foreach:

<?php

$n = 1000000

$array = [
    'one'   => 'This is the first',
    'two'   => 'This is the second',
    'three' => 'This is the third',
    'four'  => 'This is the fourth',
    'five'  => 'This is the fifth',


$start_time = microtime(true
$start_mem  = memory_get_usage(true

for ($i = 0 $i < $n $i++)
{
    unset($array_keys
    $array_keys = array_keys($array
}

$time = microtime(true) - $start_time
$mem  = memory_get_usage(true) - $start_mem

echo "array_keys()t{$time}t{$mem}n"

$start_time = microtime(true
$start_mem  = memory_get_usage(true

for ($i = 0 $i < $n $i++)
{
    unset($array_keys

    foreach ($array as $key => $value)
    {
        $array_keys[] = $key
    }
}

$time = microtime(true) - $start_time
$mem  = memory_get_usage(true) - $start_mem

echo "foreach()t{$time}t{$mem}n"

One improvement would be to track the average time per iteration as well as the
fastest and slowest iteration. I went ahead and threw the code in a
GitHub gist in case anyone wants to fork and improve upon it.

Benchmarking PHP code

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