title: Do you need to manually remove a connection from a SignalR group on disconnect?
body: <p>In a SignalR hub, I am adding connections to groups in the <code>OnConnected</code> method:</p>
  
  <pre><code>public override Task OnConnected()
  {
      this.Groups.Add(this.Context.ConnectionId, "aGroup");
      this.Groups.Add(this.Context.ConnectionId, "bGroup");
  }
  </code></pre>
  
  <p>Do I need to manually remove the connection from these groups upon disconnect? Given the pub-sub model, I don't see how I could easily do this, except to keep track of connections and groups in a separate data structure.</p>
  
  <p>I am experiencing a rather large memory leak in an MVC project using SignalR, and am wondering if this could be the culprit.</p>