title: What the frequency of the Garbage Collection in Java?
body: <p>Page 6 of the the document <a href="http://www.oracle.com/technetwork/java/javase/memorymanagement-whitepaper-150215.pdf" rel="noreferrer">Memory Management in the Java
  HotSpot™ Virtual Machine</a> contains the following paragraphs:</p>
  
  <blockquote>
    <p>Young generation collections occur relatively frequently and are
    efficient and fast because the young generation space is usually small
    and likely to contain a lot of objects that are no longer referenced.</p>
    
    <p>Objects that survive some number of young generation collections are
    eventually promoted, or tenured, to the
        old generation. See Figure 1. This generation is typically larger than the young generation and its occupancy
        grows more slowly. As a result, old generation collections are infrequent, but take significantly longer to
        complete</p>
  </blockquote>
  
  <p>Could someone please define what "<em>frequent</em>" and "<em>infrequent</em>" mean in the statements above? Are we talking <strong>microseconds, milliseconds, minutes, days</strong>?</p>