sclass BenchForNSeconds {

  settable Runnable action;

  settable double seconds; // how many seconds to run the benchmark

  volatile bool done;

  gettable long iterations;

  long startTime, endTime;

  gettable new AverageAndMinMax stats;

  *() {}

  *(double *seconds, Runnable *action) {}

  run {

    startTime = sysNanos();

    endTime = lround(startTime+secondsToNanos(seconds));

    long time = sysNanos();

    while (time < endTime) {

      action?.run();

      long runTook = sysNanos()-time;

      ++iterations;

      stats.add(runTook);

      ping();

      time = sysNanos();

    }

    endTime = time;

    set done;

  }

  S formatNanos(double nanos) { ret n2_round(nanos) + " ns"; }

  toString {

    ret stats.isEmpty() ? "Not run"

      : "min/avg/max="

        + n2_round(stats.min()) + "/"

        + n2_round(stats.avg()) + "/"

        + n2_round(stats.max()) + " ns"

        + appendRoundBracketed(nRuns((long) stats.n()));

  }

  double min() { ret stats.min(); }

}