function fillBar() {
  var arr = []
  for (var i=0; i<servers.length; i++) {
    arr.push(Math.round(Math.random()*10))
  }
  bar.setData({titles: servers, data: arr})
}
Donut Options
  self.options.radius = options.radius || 14; // how wide is it? over 5 is best
  self.options.arcWidth = options.arcWidth || 4; //width of the donut
  self.options.yPadding = options.yPadding || 2; //padding from the top