[re: davidanthoff] Thanks, David, for the Feather correction. Feather.materialize did not work for me, either, but FeatherFiles did. Its performance was about 130 seconds. This is better than the 300 second deserialization time and 600 second CSV.read time. However, this still seems poor. R takes about 30 seconds.
I also just posted my serialization experience in De-Serialization Performance .