Benchmark PHP mysql vs PHP mysqli

In PHP coding, many of my php scripts are still using php mysql extension. Before taking the time to migrate to php mysqli extension, I have decided to run a simple benchmark between the two. I have written 2 scripts and time it. The first script is "test_mysql.php", the second script is "test_mysqli.php". The result is, the first script took an average of 1.01 sec, the second script took 0.86 sec. "test_mysqli.php" is 17.87% faster than "test_mysql.php".

The scripts were tested on Linux 3.8.4, PHP 5.4.12, MySQL 5.5.30.

First script, test_mysql.php

<?php
//-----Start Timer-------------------------------------------------//       
    $time = microtime();
    $time = explode(" ", $time);
    $time = $time[1] + $time[0];
    $top = $time;
//-----Start Timer-------------------------------------------------//   
for($j=0;$j<1000;$j++)
{  
    $link = mysql_connect($host,$user,$password) or die('Error in Server information');   
    mysql_select_db($db,$link) or die('Can not Select Databasse');   
    $query="select * from com_list where field1='value1';";
    $res = mysql_query($query);  //1 is ok
    if (!$res) {
        die('Invalid query: ' . mysql_error()); }

    while($row = mysql_fetch_array($res)){
    $i++;
    }
    mysql_free_result($res);
    mysql_close($link);
}
    echo "Total lines :".$i;
//-----End Timer-------------------------------------------------//   
    $time = microtime();
    $time = explode(" ", $time);
    $time = $time[1] + $time[0];
    $bottom = $time;
//-----End Timer-------------------------------------------------//
    $loadtime = ($bottom-$top);
    echo ("<br> <br>This page generated in $loadtime seconds");  
?>

Second script, test_mysqli.php

<?php
//-----Start Timer-------------------------------------------------//       
    $time = microtime();
    $time = explode(" ", $time);
    $time = $time[1] + $time[0];
    $top = $time;
//-----Start Timer-------------------------------------------------//       
for($j=0;$j<1000;$j++)
{  
    $link = mysqli_connect($host,$user,$password,$db) or die('Error in Server information');
    $query="select * from com_list where field1='value1';";
    $res = mysqli_query($link,$query);  //1 is ok
    if (!$res) {
        die('Invalid query: ' . mysql_error()); }
    while($row = mysqli_fetch_array($res)){        
    $i++;
    }   
    mysqli_free_result($res);
    mysqli_close($link);
}
    echo "Total lines :".$i;
//-----End Timer-------------------------------------------------//       
    $time = microtime();
    $time = explode(" ", $time);
    $time = $time[1] + $time[0];
    $bottom = $time;
//-----End Timer-------------------------------------------------//           
    $loadtime = ($bottom-$top);
    echo ("<br> <br>This page generated in $loadtime seconds");  
?>