public void appendPrometheusEntry(StringBuilder builder, long timestamp) {
            builder.append(metricName)
                    .append(dimensions)
                    .append(" ").append(sanitizeIfDouble(value)).append(" ")
                    .append(timestamp).append("\n");
        }
Produces a flat list of metric entries from a snapshot (which organizes metrics by dimensions)
container-core/src/main/java/com/yahoo/container/jdisc/state/StateHandler.java