Hi all, Python 2.7 won't be maintained past 2020 and that's why we want to migrate all Python performance tests in Beam from Python 2.7 to Python 3.7. However, I was surprised by seeing that after switching Dataflow tests to Python 3.x they are a few times slower. For example, the same ParDo test that takes approx. 8 minutes to run on Python 2.7 needs approx. 21 minutes on Python 3.x. You can find all the results I gathered and the setup here <https://docs.google.com/document/d/187CO_BSqWeWLTTBrZJp0SjU3pHMRwM4SCdEXykIJp-4/edit?usp=sharing> .
Do you know any possible reason for this? This issue makes it impossible to do the migration, because of the limited resources on Jenkins (almost every job would be aborted). Thanks, Kamil
