title: Multiple Redis Instances
body: <p>Most folks seem to recommend running separate Redis instances on different ports (6379 and 6380). Why is this more commonly recommended over creating a second database? I'm not completely through the documentation yet, but most examples don't really mention 'selection of a Redis database' when connecting. An example from the Ruby client, nrk/predis's README:</p>
  
  <pre><code>$redis = new Predis\Client(array(
      'scheme' =&gt; 'tcp',
      'host'   =&gt; '10.0.0.1',
      'port'   =&gt; 6379,
  ));
  </code></pre>
  
  <p>We currently run Hubot in our office with Campfire, and I'm working on a second one for GTalk since you can only have a single adapter in use for each Hubot instance. So I'm considering creating a second database or instance of Redis so that data between the two hubots is isolated. But before I got much further, I wanted to understand why you would use separate instances instead of just creating a second database.</p>