Ah, one more thing -- there's a patch by Marina Polyakova (in CC) to make pgbench logging more regular. Maybe that stuff should be considered now too. I'm not saying to patch pgbench in this commit, but rather to have pgbench in mind while discussing the API. I think the last version of that was here:
https://postgr.es/m/a1bd32671a6777b78dd67b95eb68f...@postgrespro.ru -- Álvaro Herrera https://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
