@Override
    public void in(Metrics metrics) {
        final var isExpired = metricsDAO.isExpiredCache(model, metrics, System.currentTimeMillis(), metricsDataTTL);
        if (isExpired && !isTestingTTL) {
            log.debug("Receiving expired metrics: {}, time: {}, ignored", metrics.id(), metrics.getTimeBucket());
            return;
        }
        aggregationCounter.inc();
        dataCarrier.produce(metrics);
    }
Accept all metrics data and push them into the queue for serial processing
oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/worker/MetricsPersistentWorker.java