persistable sclass TickerSequence {
  new LongBuffer timestamps;
  new DoubleBuffer prices;
  
  void add(double price, long timestamp) {
    timestamps.add(timestamp);
    prices.add(price);
  }
  
  void add(double[] prices, long[] timestamps) {
    this.prices.addAll(prices);
    this.timestamps.addAll(timestamps);
  }
}