presto-main/src/main/java/io/prestosql/execution/SqlTaskManager.java/SqlTaskManager/getTaskResults
class SqlTaskManager:    @Override
    public ListenableFuture<BufferResult> getTaskResults(TaskId taskId, OutputBufferId bufferId, long startingSequenceId, DataSize maxSize)
    {
        requireNonNull(taskId, "taskId is null");
        requireNonNull(bufferId, "bufferId is null");
        checkArgument(startingSequenceId >= 0, "startingSequenceId is negative");
        requireNonNull(maxSize, "maxSize is null");

        return tasks.getUnchecked(taskId).getTaskResults(bufferId, startingSequenceId, maxSize);
    }