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Re: Rename max_parallel_degree?

Peter Geoghegan <pg@heroku.com>

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From: Peter Geoghegan <pg@heroku.com>
To: Josh berkus <josh@agliodbs.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Robert Haas <robertmhaas@gmail.com>, Noah Misch <noah@leadboat.com>, David Rowley <david.rowley@2ndquadrant.com>, Amit Kapila <amit.kapila16@gmail.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Magnus Hagander <magnus@hagander.net>, Bruce Momjian <bruce@momjian.us>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2016-05-31T17:16:56Z
Lists: pgsql-hackers 
On Tue, May 31, 2016 at 10:10 AM, Josh berkus <josh@agliodbs.com> wrote:
> "max_parallel_degree is the amount of parallelism in the query, with the
> understanding that the original parent process counts as 1, which means
> that if you set it to 1 you get no parallelism, and if you want 4
> parallel workers you need to set it to 5."
>
> Which one of those is going to require more explanations on -general and
> -novice?  Bets?
>
> Let's not be complicated for the sake of being complicated.

But the distinction between parallel workers and backends that can
participate in parallel query does need to be user-visible. Worker
processes are a commodity (i.e. the user must consider
max_worker_processes).

-- 
Peter Geoghegan