PHP list+explode VS substr+strpos - what is more efficient?

Question

Sample text:

$text = 'Administration\Controller\UserController::Save';

Task - extract everything before ::

Option 1:

list($module) = explode('::',$text);

Option 2:

$module = substr($text, 0, strpos($text, '::');

Which option is more efficient?

Answer 1

On my system:

~/pb$ uname -a && php -v
Linux hostname 3.2.0-4-amd64 #1 SMP Debian 3.2.46-1+deb7u1 x86_64 GNU/Linux
PHP 5.4.19-1~dotdeb.1 (cli) (built: Aug 27 2013 00:42:43) 
Copyright (c) 1997-2013 The PHP Group
Zend Engine v2.4.0, Copyright (c) 1998-2013 Zend Technologies
    with XCache v3.0.3, Copyright (c) 2005-2013, by mOo
    with Xdebug v2.2.3, Copyright (c) 2002-2013, by Derick Rethans
    with XCache Cacher v3.0.3, Copyright (c) 2005-2013, by mOo

I have results:

~/pb$ ./test ListVsSubstr
[============================================================>] 1000 u | 8134 u/s | Est: 0.0 s | Mem: 335.74 KB | Max: 357.96 KB
[============================================================>] 1000 u | 7808 u/s | Est: 0.0 s | Mem: 336.14 KB | Max: 357.96 KB
Test name       Repeats         Result          Performance 
list+explode    1000            0.044890 sec    +0.00%
substr+strpos   1000            0.052825 sec    -17.68%

Test code here: link. From time to time results slightly different, but list+explode is always faster more than 15%.

Different systems and PHP versions may have different results. You must check it by yourself and for sure in environment configuration identical to your production.

Answer 2

I ran a test and seems like the first solution is faster. Here is the code for testing it:

function microtime_float()
{
    list($usec, $sec) = explode(" ", microtime());
    return ((float)$usec + (float)$sec);
}

function solution1($text)
{
    for($i = 0; $i < 10000; $i++)
        list($module) = explode('::',$text);
}

function solution2($text)
{
    for($i = 0; $i < 10000; $i++)
        $module = substr($text, 0, strpos($text, '::'));
}

$text = 'Administration\Controller\UserController::Save';

$time_start = microtime_float();

solution1($text);

$time_end = microtime_float();
$time = $time_end - $time_start;

echo "Did solution1 in $time seconds.\n";

$time_start = microtime_float();

solution2($text);

$time_end = microtime_float();
$time = $time_end - $time_start;

echo "Did solution2 in $time seconds.\n";

Test 1: Did solution1 in 0.19701099395752 seconds. Did solution2 in 0.38502216339111 seconds.

Test 2: Did solution1 in 0.1990110874176 seconds. Did solution2 in 0.37402105331421 seconds.

Test 3: Did solution1 in 0.19801092147827 seconds. Did solution2 in 0.37002205848694 seconds.