private void printMetrics(PrintStream out, RouteMetricSet metrics) {
        for (MessageTypeMetricSet m : metrics.getMetrics().values()) {
            long timeUsed = timer.milliTime() - startTime;
            out.println(timeUsed + ", " + m.count + ", " + m.errorCount + ", " + m.latency_min + ", " + m.latency_max + ", " + m.latency_total/Long.max(1L, m.count));
        }
    }
Class that takes progress from the feed and prints to a stream.
vespaclient-java/src/main/java/com/yahoo/vespafeeder/BenchmarkProgressPrinter.java