CODEWITHSUNDEEP
phpmemcachedcodeigniter-3
Oleksandr IY
Oleksandr IY

Reputation: 3126

Codeigniter memcached driver: slow work on lock

I turned on memcached on codeigniter. It works fine but I noticed some delay on script execution. I debugged Session_memcached_driver and figured that it stuck for a few seconds on line 330-336

    do
    {
        if ($this->_memcached->get($lock_key))
        {
            sleep(1);
            continue;
        }

        if ( ! $this->_memcached->set($lock_key, time(), 300))
        {
            log_message('error', 'Session: Error while trying to obtain lock for '.$this->_key_prefix.$session_id);
            return FALSE;
        }

        $this->_lock_key = $lock_key;
        break;
    }
    while (++$attempt < 30);

Obviously, it waiting for release and that takes a few seconds(5-7 seconds). Maybe I don't close something what I should or use CI session mechanism in wrong way? PHP 7, Linux, CI 3.1.4

Upvotes: 0

Views: 548

Answers (1)

Dainius Pocius
Dainius Pocius

Reputation: 21

I had absulutely the same issue. Delay is caused by touch() command. If you look at driver line 109:

$this->_memcached->setOption(Memcached::OPT_BINARY_PROTOCOL, TRUE);

Comment out temporarily to see, if it solves issue. if YES, you need to update libmemcached on server. After upgrade, restart web server .

I had libmemcached 1.0.16, upgraded to 1.0.18 If you DONT upgrade, but just comment out that line, session time will NOT be extended upon user activity and will expire faster - as defined by config file.

Good luck!

Upvotes: 1

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