Pulse of Garbage Collector in V8. See more: https://www.youtube.com/watch?v=ZAJmJmKWNPw

GC Pulse on JS

getFakeHistory = function(){
  return (new Array(20000).join('a'))
}

function Record(id, description) {
  this.id = id;
  this.description = description;
}

# We need that function to prevent V8 optimisation 
Record.prototype.doMagic = function(){ 
  return this.id + 1
}

var sum = 0;

for (var i = 0; i < 10000; i++){
  console.time('create')
  var record = new Record(i, getFakeHistory());
  sum  += record.doMagic();
  console.timeEnd('create')
}

# => 
-> 0.03369140625ms
-> 0.033935546875ms
-> 0.034912109375ms
-> 0.0341796875ms
-> 0.03271484375ms
-> 0.046142578125ms
+> 0.26611328125ms
-> 0.0380859375ms
-> 0.034912109375ms
-> 0.03466796875ms
-> 0.033935546875ms
-> 0.03369140625ms
-> 0.035888671875ms
-> 0.034912109375ms
+> 0.242919921875ms
-> 0.034912109375ms
-> 0.03369140625ms
-> 0.03515625ms
-> 0.032958984375ms
-> 0.033935546875ms
-> 0.034912109375ms
-> 0.031982421875ms
+> 0.241943359375ms
-> 0.032958984375ms
-> 0.0322265625ms


Solution is to allocate object before the loop and store them inside global variable,
So you restrict that object for GC circle _

for (var i = 0; i < 10000; i++) {
  records[i] = new Record()
}
...