gistfile1.php

<?php
// In controller...
public function getReportAcrossDatabasesAction(Request $request)
{
  // Listen for Gearman to notify that it has data from a completed job.
  $this->get('event_dispatcher')
       ->addListener('gearman.client.callback.complete',array($this,'gearmanCallback'));
  
  $gearman = $this->get('gearman');
  
  //Assume $request->request->get('connectionIds') is list of connections.
  foreach($request->request->get('connectionIds') as $connID)
  {
    $gearman->addTask('MyDemoBundleWorker~gatherVastAmountsOfData',array(json_encode('connection_id'=>$connId)));
  }
  
  $gearman->runTasks();
  
  $totalRowCount = 0;
  
  foreach($this->callbackData as $data)
  {
    $totalRowCount+= $data['total'];  
  }
  
  return array('totalRowCount'=>$totalRowCount);
}


public function gearmanCallback(GearmanClientCallbackCompleteEvent $e)
{
    $this->callbackData[]  = json_decode($e->getGearmanTask()->data(),true);
}