presto-main/src/main/java/io/prestosql/split/BufferingSplitSource.java/BufferingSplitSource/getNextBatch
class BufferingSplitSource:    @Override
    public ListenableFuture<SplitBatch> getNextBatch(ConnectorPartitionHandle partitionHandle, Lifespan lifespan, int maxSize)
    {
        checkArgument(maxSize > 0, "Cannot fetch a batch of zero size");
        return GetNextBatch.fetchNextBatchAsync(source, Math.min(bufferSize, maxSize), maxSize, partitionHandle, lifespan);
    }