title: Difference between a JVM with and without JIT
body: <p>I am referring to the below document by Oracle:</p>
  
  <p><a href="http://docs.oracle.com/cd/E13150_01/jrockit_jvm/jrockit/geninfo/diagnos/underst_jit.html#wp1080014" rel="nofollow noreferrer">http://docs.oracle.com/cd/E13150_01/jrockit_jvm/jrockit/geninfo/diagnos/underst_jit.html#wp1080014</a></p>
  
  <p>It is mentioned in the "1. The JRockit JVM Runs JIT Compilation " section that the JIT JVM has more startup time and less execution time and vice-versa for JVMs without JIT.</p>
  
  <p>I am confused because as per my knowledge, JIT compiles the code as per the execution of program therefore making the compilation fast. And the code will be optimized so execution time will be fast as well. </p>
  
  <p>What do they want to signify with this point? I am not understanding it properly.</p>