What is process.memory giving ?

Gave it a new try and got these numbers:
blinker object only, usage 50, history 37
3 blinker with object, usage 158, history 49
3 blinker with object, minified from 504 to 386, usage 149, history:31
3 blinker with require, usage 192, history:55
From my best understanding

• the blinker object itself takes a few bytes only
  
• each instance with 4 variables(pin,duration,interval,status) takes around 600 bytes
  
• minifying reduces some bytes
  

• require takes more memory than an object
  Is there anything wrong with my interpretation ?

  
  function Blinker(pin,frequency){
  this.interval = 0;
  this.status = true;
  this.duration = 1000 / frequency;
  this.pin = pin;
  this.start();
  }
  Blinker.prototype.start = function(){
  var me = this;
  me.interval = setInterval(function(){
  me.status = !me.status;
  me.pin.write(me.status);
  },me.duration);
  };
  Blinker.prototype.stop = function(){
  this.pin.write(false);
  clearInterval(this.interval);
  };
  var b = new Blinker(LED1,2);
  var c = new Blinker(LED2,5);
  var d = new Blinker(LED3,7);