write to swapfile on rbuf_flush

class Metric(key: MetricKey) {

  val bucket = BucketFactory.new_bucket(key.mode)

  val swap = new SwapFile(key)

  var rbuf = new RingBuffer[(Long, Double)](1000)

  var rbuf_seek_pos = 0

    }

    rbuf.push(((time, value)))

    //println("RINGBUF", rbuf.tail(10))

    flush_rbuf // FIXPAUL: remove me

  }

  // tries to persist as much data from the in memory ring buffer to disk

  // as possible but doesnt remove it from the buffer yet

  def flush_rbuf = this.synchronized {

    val flush_range = rbuf.size - rbuf_seek_pos

    //println("RBUF_FLUSH", rbuf.tail(flush_range))

    for (sample <- rbuf.tail(flush_range))

      swap.put(sample._1, sample._2)

    swap.flush

    rbuf_seek_pos += flush_range

  }

class SwapFile(metric_key: MetricKey) {

  var write_pos = 0

  val file_name = "metric-" + metric_key.key +

    metric_key.mode + "-" + metric_key.flush_interval

  }

  def flush : Unit = {

    file.seek(file.length)

    file.seek(write_pos)

    file.write(buffer.array)

    write_pos += 18

    buffer.rewind

  }