title: Setting celery concurrency to 1 worker per queue
body: <p>I am essentially using rabbitmq queues in celery as a poor man's synchronisation.  Eg when certain objects are updated (and have a high cost), I round robin them to a set of 10 queues based on their object IDs.  Firstly is this a common pattern or is there a better way.</p>
  
  <p>Secondly, with celeryd, it seems that the concurrency level option (CELERY_CONCURRENCY) sets the number of workers across all the queues.  This kind of defeats the purpose of using the queues for synchronization as a queue can be serviced by multiple workers, which means potential race conditions when performing different actions on the same object.</p>
  
  <p>Is there a way to set the concurrency level (or worker pool options) so that we have one worker per N queues?  </p>
  
  <p>Thanks
  Sri</p>