presto-main/src/main/java/io/prestosql/server/remotetask/HttpRemoteTask.java/HttpRemoteTask/noMoreSplits
class HttpRemoteTask:    @Override
    public synchronized void noMoreSplits(PlanNodeId sourceId, Lifespan lifespan)
    {
        if (pendingNoMoreSplitsForLifespan.put(sourceId, lifespan)) {
            needsUpdate.set(true);
            scheduleUpdate();
        }
    }