title: Specific meanings of jstat parameters : YGCT FGCT GCT
body: <p>I need to use jstat to measure some GC parameters of a program. Jstat provides set of parameters ( S0C S1C S0U S1U EC EU OC OU MC MU CCSC CCSU YGC YGCT FGC FGCT GCT)
  From those I am bit confused with the descriptions for  YGCT, FGCT and GCT.</p>
  
  <p>(YGCT    Young generation garbage collection time.<br>
  FGCT    Full garbage collection time.<br>
  GCT     Total garbage collection time.)</p>
  
  <p>I have 2 questions.</p>
  
  <p>1) What does these three parameters (YGCT, FGCT and GCT) actually measure? A small comparison would be very helpful</p>
  
  <p>2) I how can I know the unit of time that they are mentioning? (milliseconds/ seconds/.... )</p>
  
  <p>I referred many documentations including</p>
  
  <p><a href="https://stackoverflow.com/questions/14464987/interpreting-jstat-results">Interpreting jstat results</a><br>
  <a href="http://www.cubrid.org/blog/dev-platform/how-to-monitor-java-garbage-collection/" rel="nofollow noreferrer">http://www.cubrid.org/blog/dev-platform/how-to-monitor-java-garbage-collection/</a><br>
  <a href="http://docs.oracle.com/javase/6/docs/technotes/tools/share/jstat.html#output_options" rel="nofollow noreferrer">http://docs.oracle.com/javase/6/docs/technotes/tools/share/jstat.html#output_options</a><br>
  But these does not answer my real question.<br>
  Could anyone how has experienced with jstat help me with this?</p>
  
  <p>Thank you.  </p>