title: Impala - Let Impala pick its own memory limit
body: <p>I have Cloudera Express 5.3.2 installed on a cluster. I would like to use it for Impala querying.</p>
  
  <p>I want to let Impala set the limit depending on the cluster's capacity. In the Impala configuration, in cloudera manager, it's written to "leave it blank to let Impala pick its own limit".  However I can't leave the field blank because the web interface tells me that "this field is required".</p>
  
  <p><a href="http://i.imgur.com/c9RA8mV.png" rel="nofollow">http://i.imgur.com/c9RA8mV.png</a></p>