presto-main/src/main/java/io/prestosql/execution/scheduler/FixedSourcePartitionedScheduler.java/FixedSourcePartitionedScheduler/startLifespan
class FixedSourcePartitionedScheduler:        @Override
        public void startLifespan(Lifespan lifespan, ConnectorPartitionHandle partitionHandle)
        {
            pendingCompleted.add(lifespan);
            if (started) {
                return;
            }
            started = true;
            sourceScheduler.startLifespan(Lifespan.taskWide(), NOT_PARTITIONED);
            sourceScheduler.noMoreLifespans();
        }