title: Why garbage collector stops all the threads before reclaiming the memory
body: <p>I was reading some performance related post, and then I encountered the sentence "<strong>Java's garbage collector stops all the threads before reclaiming the memory, which is also a performance issue</strong>". I tried to find it on Google, but I could not.</p>
  
  <p>Could someone please share something so that I can be clear about this?</p>