This is an interesting benchmark I'll try to code up. Although, it seems a bit like an apples/oranges comparison, since a Dataframe in memory had to come from somewhere, either a CSV or database like Postgres, in which case I have my money on Postgres outcompeting the standalone process parsing CSV.

In the end though, it'll be important to have benchmarks for all the key steps in the process, both in terms of memory and compute. Off a hunch, I think the memory inefficiency involved in high level pandas operations is more likely to be a driving force to move operations into lower layers, than CPU runtime.