/**
* Do garbage collection for session tracking information.
*/
public function trackGC()
{
$this->_hash->lock($this->_trackID);
if ($ids = $this->_getTrackIds()) {
$alter = false;
foreach (array_keys($ids) as $key) {
if (!$this->_hash->exists($key)) {
unset($ids[$key]);
$alter = true;
}
}
if ($alter) {
$this->_hash->set($this->_trackID, json_encode($ids));
}
}
$this->_hash->unlock($this->_trackID);
}