title: Thread Pooling in Grails Controllers and Services
body: <p>I'm wondering how controllers and services are implemented in Grails. In particular I would like to know, whether and how it maintains a thread pool for both controllers and services.</p>
  
  <p>Assuming following scenario:</p>
  
  <blockquote>
    <p>I have a Grails controller that calls a service that does a blocking
    call to a external system.</p>
  </blockquote>
  
  <p>Would I need to take care of maintaining a thread pool in the service (or even the controllers), so that when I have multiple user concurrently access my application, the application does not block because of a call in one service?</p>