public LatencyMetrics getLatencyMetricsAndStartNewPeriod() {
        synchronized (monitor) {
            pushEndOfPeriodToNow();
            LatencyMetrics metrics = makeLatencyMetrics();
            resetForNewPeriod();
            return metrics;
        }
    }
Returns the metrics for the current time period up to now, and starts a new period.
zkfacade/src/main/java/com/yahoo/vespa/curator/stats/LatencyStats.java