var showMem = function() {
     var mem = process.memoryUsage();
     var format = function(bytes) {
          return (bytes/1024/1024).toFixed(2)+'MB';
     };
     console.log('Process: heapTotal '+format(mem.heapTotal) + ' heapUsed ' + format(mem.heapUsed) + ' rss ' + format(mem.rss));
     console.log('----------------------------------------');
};

var useMem = function () {
     var size = 20*1024*1024;
     var arr = new Array(size);
     for (var i=0;i<size;i++) {
          arr[i] = 0;
     }
     return arr;
};

var total = [];

for (var j=0;j<15;j++) {
     showMem();
     total.push(useMem());
}
showMem();