I am building a task module, to do time consuming jobs in background. A worker instance is constantly pooling redis db for a new task. However after first connection, somehow rediska (a php redis client) closes connection, and when I make query to db, it automatically creates a new connection using default settings. At this point new connection is not using the settings in the configuration. It is using hard coded default values. I don’t know why it is doing this but here is the solution.

Whenever you use a rediska key, explicitly tell the instance name you want to use.
$option = array("rediska"=>"use_this_instance_name");
$pointer = new Rediska_Key("job:$index:pointer",$option);

To define aforementioned rediska instance:

$options = array (
                    'addToManager' => true,
                    'name'         => "use_this_instance_name",
                    'namespace'    => '',
                    'servers'      => array(
                        array(
                            'host'   => Rediska_Connection::DEFAULT_HOST,
                            'port'   => Rediska_Connection::DEFAULT_PORT,
                            'weight' => Rediska_Connection::DEFAULT_WEIGHT,
                            'db'=>2,
                            'persistent'=>TRUE,
                            'timeout'=>0
                            
                        )
                    )  
                );
$redis = new Rediska($options);