title: Is private memory slower than local memory?
body: <p>I was working on a kernel which had much global memory access per thread so I copied them to local memory which gave a speed up of 40%.</p>
  
  <p>I wanted still more speed up so copied from local to private which degraded the performance</p>
  
  <p>So is it correct that I think we must not use to much private memory which may degrade the performance?</p>