title: UIView self.layer.shouldRasterize = YES and performance issues
body: <p>I would like to share my experience from using <code>self.layer.shouldRasterize = YES;</code> flag on UIViews.</p>
  
  <p>I have a <code>UIView</code> class hierarchy that has <code>self.layer.shouldRasterize</code> turned <strong>ON</strong> in order to improve scrolling performance (<strong>all of them have STATIC subviews that are larger than the screen of the device</strong>). </p>
  
  <p>Today in one of the subclasses I used <code>CAEmitterLayer</code> to produce nice particle effects.</p>
  
  <p>The <strong>performance is really poor</strong> although the number of particles was really <strong>low (50 particles)</strong>.</p>
  
  <p>What is the cause of this problem?</p>