fork + PHP CodeIgniter: 'MySQL server has gone away' - How not to lose connection when forking with CI?

问题

I installed fork on my Ubuntu Server (using PHP-Apache-Codeigniter).

I have this code:

<?php 

public function add_keyword() {

    $keyword_p = $this->input->post('key_word');

    $prod      = $this->input->post('prod_name');
    $prod      = $this->kas_model->search_prod_name($prod);
    $prod      = $prod[0]->prod_id;

    $country   = $this->input->post('key_country');

    $keyword = explode(", ", $keyword_p);
    var_dump($keyword); 
    $keyword_count = count($keyword);
    echo "the keyword count: $keyword_count";

    // Create   fork
    $pid = pcntl_fork();
    if(!$pid){

        for ($i=0; $i < $keyword_count ; $i++) { 

            // Inserts the inputs to the "keywords" table
            $this->kas_model->insert_keyword($keyword[$i], $prod, $country);

            // Gets relevant IDs for the inserted prod and keyword
            $last_inserted_key = $this->kas_model->get_last_rec('keywords');
            $keyword_id        = $last_inserted_key[0]->key_id;
            $prod_id           = $last_inserted_key[0]->key_prod;
            $prod_id_query     = $this->kas_model->get_prod_row_by_id($prod_id);
            $prod_id_a  = $prod_id_query[0]->prod_a_id;
            $prod_id_b  = $prod_id_query[0]->prod_b_id; 

            // Run the keyword query (on API) for today on each one of the keys and insert to DB aslong that the ID isn't 0.  
            if ( ($prod_id_a != 0) || ( !empty($prod_id_a) ) ) {
                $a_tdr = $this->get_var1_a_by_id_and_kw( $prod_id_a, $keyword[$i], $country);
            } else {
                $a_tdr['var1'] = 0;
                $a_tdr['var2'] = 0;
                $a_tdr['var3'] = 0;
            }

            if ( ($prod_id_b != 0) || ( !empty($prod_id_b) ) ) {
                $b_tdr = $this->get_var1_b_by_id_and_kw($prod_id_b, $keyword[$i], $country);
            } else {
                $b_tdr['var1'] = 0;
                $b_tdr['var2'] = 0;
                $b_tdr['var3'] = 0;     
            }

            $this->kas_model->insert_new_key_to_db($keyword_id, $a_tdr['var1'], $b_tdr['var1'], $a_tdr['var2'], $b_tdr['var2'], $a_tdr['var3'], $b_tdr['var3']);

        }
        exit($i);
    }


    redirect('main/kas'); 
}

What the function does: This function gets 1 or more keyword/s, a country var, and a product ID, and runs a query on an external slow API getting variables (runs other functions from within that same controller), and adds them to the database.

Solution: When running this function, and if I insert a lot of keywords, the page loads, and loads, and loads, for a long time, until it's done, and only then - I can continue browsing my website. So I was told to fork it since it's just sending a request to process it in the background, so whenever clicking the submit button, I get redirected to "main/kas".

Currently: I get the my MySQL connection disconnected with this error:

MySQL server has gone away

But with inserting 1 var from all the process.

What I trird till now: As said in this comment: http://www.php.net/manual/en/function.pcntl-fork.php#70721

I have to reconnect to my DB in the parent, and that should solve the problem. I have found this post from 2009 too: Sudden "MySQL server has gone away" error in PHP site

So I continued my "if" with this:

// parent    
} else if ( $pid ) {
        $this->load->database(); 
        $this->db->reconnect();
    }

I tried adding this in the end of the child too (frustration) and in all sorts of variations (regular $link = mysqli_connect("127.0.0.1", "my_user", "my_password", "my_db");) - no success.

Even tried using only $this->load->database(); or only $this->db->reconnect();.

What is the solution for this, this is so frustrating :'(

来源：https://stackoverflow.com/questions/36764349/fork-php-codeigniter-mysql-server-has-gone-away-how-not-to-lose-connectio