title: What does "cacheline aligned" mean?
body: <p>I read this article about PostgreSQL performance: <a href="http://akorotkov.github.io/blog/2016/05/09/scalability-towards-millions-tps/" rel="noreferrer">http://akorotkov.github.io/blog/2016/05/09/scalability-towards-millions-tps/</a></p>
  
  <p>One optimization was "cacheline aligment".</p>
  
  <p>What is this? How does it help and how to apply this in code?</p>