Sessions in database other than default?

Anyone have any ideas on the best way of going about storing ci_sessions on a database other than the default database?

Thanks

What is "the default database"? ...in your view...

Website: http://avenir.ro

What is "the default database"? ...in your view...

The one that is set in database.php by $db['default'].

Do you mean the default database connection or the default schema (which MySQL ambiguously calls "database")?

Using another schema should be easy.
Using a different connection is ... technically possible, but doesn't make sense.

I mean another connection. Our application is currently load balanced across 3 web servers with 2 database shards. The database we have set as the main connection handles the majority of transdactions/data storage.

With the addition of ci_sessions to our "default connection" when we have spikes in traffic we see some performance issues as well as a spike in active threads mainly due to a stuck GET_LOCK query on the ci_sessions table.

So I am looking to move this table over to its own database to see if it helps.

It won't help ... You're shooting in the dark here and that rarely yields positive results.

IMO, those GET_LOCK() queries aren't stuck ... they're waiting for RELEASE_LOCK() calls from other processes. To improve on that - call session_write_close() as soon as you no longer need to write new session data.

If you still want to try, there's a little trick ...

The documentation says you have to use the default connection because that's the one connection that's almost guaranteed to exist, but technically it just looks for get_instance()->db (and loads the 'default' connection if that doesn't exist) and creates a copy of it. So you can do something like this:

Code:

$this->default_db = $this->db;
unset($this->db);
$this->db = $this->load->database('session', TRUE);
$this->load->library('session');
$this->db = $this->default_db;
unset($this->default_db);

I wouldn't get my hopes up though ... I don't see how moving sessions to another database would help - GET_LOCK() will still block new requests until the lock is released.