Using force_parallel_mode Correctly

I admit it: I invented force_parallel_mode.  I believed then, and still believe now, that it is valuable for testing purposes.  Certainly, testing using force_parallel_mode=on or force_parallel_mode=regress has uncovered many bugs in PostgreSQL's parallel query support that would otherwise have been very difficult to find.  At the same time, it's pretty clear that this setting has caused enormous confusion, even among PostgreSQL experts.  In fact, in my experience, almost everyone who sets force_parallel_mode is doing so for the wrong reasons.

Who Contributed to PostgreSQL Development in 2017?

Last year, I wrote a post on who contributed to PostgreSQL development in 2016.  This is a (belated) version of the same information for 2017.  I used the same methodology this time for analyzing the commit log as I did last year.