IIRC, it took me 4-7 hours to load 600GB of uncompressed data to the PostgreSQL after disabling WAL and tunning some config variables. I didn't have time to test all possible speed improvements.

After import, it takes 3-6 hours additionally to create indexes for those tables.

I think the main problem was that I had text indices. I'm not an expert in RDBMS and used a simple join that was taking ages to start producing the actual data. There are definitely a lot of ways to tune such queries and PostgreSQL configs, but I wanted a simple and universal solution.