code: public function getObservers()
      {
          if ($this->observers === null) {
              $this->observers = array();
  
              foreach ($this->getTimers() as $timerName => $timer) {
                  if (strpos($timerName, 'OBSERVER') === 0) {
                      $this->observers[] = array(
                          'name'     => $timerName,
                          'count'    => $timer['count'],
                          'sum'      => round($timer['sum'] * 1000, 2), // ms
                          'mem_diff' => $timer['realmem'] / pow(1024, 2), // MB
                      );
                  }
              }
          }
  
          return $this->observers;
      }
docs: Returns a list of called observers during request.
  Observers are determined based on Varien Profiler timers
  
  @return array