title: Redis: Is PUBLISH asynchronous?
body: <p>If I <code>PUBLISH</code> a message on Redis that has one subscriber but that subscriber takes 1 second to receive the message will is block the <code>PUBLISH</code> for one second or do they act independently?</p>
  
  <p>If they act independently how many <code>PUBLISH</code> commands will be queued before bad stuff starts happening?</p>