Problems using Codeigniter with Memcached

Question

I'm using Codeigniter 2.1.4 with PHP 5.5 in an application I manage. I've been testing Memcached to improve app's performance and it was working fine yesterday.

Today I was planning to deploy it live but after some improvements I noticed that it wasn't working anymore. On production I'll use AWS Elasticache (which is also not working on my staging environment - but the purpose of this question is to get it back running on my localhost, after that I'll worry about Elasticache).

Before everything, on MAMP's php info I see:

memcached support       enabled
Version                 2.2.0
libmemcached version    1.0.18
SASL support            yes
Session support         yes
igbinary support        no
json support            no
msgpack support         no

On codeigniter application/config/development/ I have a file called memcached.php with this content:

<?php
if (!defined('BASEPATH')) exit('No direct script access allowed');

$config = array(
    'default' => array(
        'host'      => 'localhost',
        'port'      => 11211,
        'weight'    => 1
    )
);

My test is simple. I have a controller with this function:

public function memcached(){
    $this->load->driver('cache');
    if($this->cache->memcached->is_supported()){
       $data = $this->cache->memcached->get('foo');
       if (!$data){
          echo 'cache miss!<br />';
          $data = 'bar';
          $this->cache->memcached->save('foo',$data, 60);
       }
       echo $data;
       echo '<pre>';
       var_dump($this->cache->memcached->cache_info());
       echo '</pre>';
    }
}

And the output is (always) this:

cache miss!
bar
array(1) {
  ["localhost:11211"]=>
  array(24) {
    ["pid"]=>
    int(-1)
    ["uptime"]=>
    int(0)
    ["threads"]=>
    int(0)
    ["time"]=>
    int(0)
    ["pointer_size"]=>
    int(0)
    ["rusage_user_seconds"]=>
    int(0)
    ["rusage_user_microseconds"]=>
    int(0)
    ["rusage_system_seconds"]=>
    int(0)
    ["rusage_system_microseconds"]=>
    int(0)
    ["curr_items"]=>
    int(0)
    ["total_items"]=>
    int(0)
    ["limit_maxbytes"]=>
    int(0)
    ["curr_connections"]=>
    int(0)
    ["total_connections"]=>
    int(0)
    ["connection_structures"]=>
    int(0)
    ["bytes"]=>
    int(0)
    ["cmd_get"]=>
    int(0)
    ["cmd_set"]=>
    int(0)
    ["get_hits"]=>
    int(0)
    ["get_misses"]=>
    int(0)
    ["evictions"]=>
    int(0)
    ["bytes_read"]=>
    int(0)
    ["bytes_written"]=>
    int(0)
    ["version"]=>
    string(0) ""
  }
}

The funny thing is that if I edit memcached's host address in that memcached.php config file it still outputs ["localhost:11211"] .

UPDATE:

I've just created a clean application using fresh downloaded Codeigniter 2.1.4 files and it's all the same.

Cheers!

Answer 1

You should check if the memcached service is running. Your results show a pid (process id) of -1 and an uptime of 0 seconds.

There is an actual memcached service that needs to be running on the server, you can check if it's listening properly by trying telnet to port 11211 on localhost.