Magento - Lost connection to MySQL server

I have been facing this issue for past few hours when I tried to do a bulk insert from Magento database through a custom module to our DWH. Datawarehouse is running MYSQL server on CentOS 6.2. I was doing a full dump of customers, products and orders from our Magento store to the Datawarehouse for the first time. But I couldn't  even get  more than 2k customers to the DWH database. Magento module returns an error "Error 2013 : Lost connection to MySQL server".

After doing some reading on the internet I found that, this is nothing to do with Magento or my custom module. It was just the way MYSQL server was configured.  Luckily it was a easy fix :).  Just change the max_allowed_packet parameter.

In CentOS go to /etc/my.cnf and add or edit the following under [mysqld] section

[mysqld]
max_allowed_packet= 16M 

I had 16M to suit my particular situation, choose a value that suites you. This should work, at least it worked for me ;), also recommend to have look at the wait_timeout parameter as well since few people mentioned that as well.

PHP5 DB Connection Class with MYSQLi using Singleton!

Thought it would be a good idea to share my database connection class with you all, which I use in my apps. I have implemented this class in Singleton Design Pattern.

Use of this class will help you to manage the database connection of your PHP5 application, and will avoiding you and/or your programmers creating more and more DB connection instances, that will make your code more complicated and disorganized.

As a result of using Singleton Design Pattern, no one will be able to create more than one instance of the class. So whenever anyone tries  to create an object of this class, they will either get a new object when it is the first time you are creating an object of this class, else you will always get a DB Connection instance which has already begin created.

I have made this class little bit simple to help everyone could understand it and to use when ever you need it.

Here is the code,

 /*PHP5 MYSQLi DB Connection Class implementing Singleton Design Pattern
 * 
 * Author  : Thanura Siribaddana
 * Date    : 05-APR-2010
 * Web Site: www.thanura.com
 * 
 *  Usage:
 *   $db = DBAccess::getConnection();
 *   $query = "select * from TABLE";
 *   $result=$db->selectQuery($query);
 */
error_reporting(E_NOTICE);

class DBAccess{

 const DB_SERVER="localhost"; 
 const DB_USER="root";
 const DB_PASS="pass";
 const DB_NAME="dbname";
 
 private $_connection;
 private static $_dbinstance;

/* Made the constructor private, 
* to ensures that the class can only be instantiated 
* from within itself.
*/
 private function __construct(){
  try{
   $this->_connection= new mysqli(self::DB_SERVER,
                                     self::DB_USER,
                                     self::DB_PASS,
                                     self::DB_NAME);
   if ($this->_connection->connect_error){
       throw new Exception("Could not connect to Database.");
   }
  }catch(Exception $err){
   echo $err->getMessage();
   die();
  }
  
 }
 public static function getConnection(){
  if (is_null(self::$_dbinstance)){
   self::$_dbinstance= new DBAccess();
  }
  return self::$_dbinstance;
 }
 /* Execute a SQL query and returns the results*/
 public function selectQuery($query){
  $rs=$this->_connection->query($query);
  return $rs; 
 }
}

All comments welcome!! For fine-tuning... For better ideas... any thing...