fetch too many lines and need a better fetchmany

I use pyhive in my python code, but I found that, in pyhive, fetchmany just using fetchone.
One case of my code , result has 6000000 lines, and need to export from hive drive, and I test the network latency is 0.3ms, but it still cost about 40 minutes.
Is there a better fetchmay function? In my another thrift hive driver , it use real fetchN function and much less network socket call.