presto-raptor-legacy/src/main/java/io/prestosql/plugin/raptor/legacy/util/PrioritizedFifoExecutor.java/FifoRunnableTask/compareTo
class FifoRunnableTask:        @Override
        public int compareTo(FifoRunnableTask<T> other)
        {
            return ComparisonChain.start()
                    .compare(this.task, other.task, taskComparator)
                    .compare(this.sequenceNumber, other.sequenceNumber)
                    .result();
        }