<?php
return Array
(
    "db_host1" => 123,
    "db_host2" => 123,
    "db_host3" => 123,
    "db_host4" => 123,
    "db_host5" => 123,
    "db_host6" => 123,<br/>    "db_host7" => 123,
    "db_host8" => 123,
    "db_host9" => 123,
    "db_host10" => 123,
    "db_host11" => 123,
    "db_host12" => 123,
    "db_host13" => 123,
    "db_host14" => 123,
    "db_host15" => 123,
    "db_host16" => 123
);
?>

<?php exit;?>
db_host1 =123
db_host2 =123
db_host3 =123
db_host4 =123
db_host5 =123
db_host6 =123
db_host7 =123
db_host8 =123
db_host9 =123
db_host10 =123
db_host11 =123
db_host12 =123
db_host13 =123
db_host14 =123
db_host15 =123
db_host16 =123

<?php
return
'a:16:{s:8:"db_host1";s:3:"123";s:8:"db_host2";s:3:"123";s:8:"db_host3";s:3:"123";s:8:"db_host4";s:3:"123";s:8:"db_host5";s:3:"123";s:8:"db_host6";s:3:"123";s:8:"db_host7";s:3:"123";s:8:"db_host8";s:3:"123";s:8:"db_host9";s:3:"123";s:9:"db_host10";s:3:"123";s:9:"db_host11";s:3:"123";s:9:"db_host12";s:3:"123";s:9:"db_host13";s:3:"123";s:9:"db_host14";s:3:"123";s:9:"db_host15";s:3:"123";s:9:"db_host16";s:3:"123";}';
?>

$t1 = microtime(true);

$file1 = './arr.php';
$file2 = './ini.php';
$file3 = './str.php';

for($i=0; $i<10000; $i++){
//$arr  = require $file1;
//$arr  = parse_ini_file($file2);
$arr  = unserialize(require $file3);
}

$t2 = microtime(true);
echo $t2-$t1;