Re: Rename max_parallel_degree? - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Rename max_parallel_degree?
Date
Msg-id 9816.1464715836@sss.pgh.pa.us
Whole thread Raw
In response to Re: Rename max_parallel_degree?  (Josh berkus <josh@agliodbs.com>)
Responses Re: Rename max_parallel_degree?  ("Joshua D. Drake" <jd@commandprompt.com>)
Re: Rename max_parallel_degree?  (Tom Lane <tgl@sss.pgh.pa.us>)
Re: Rename max_parallel_degree?  ("David G. Johnston" <david.g.johnston@gmail.com>)
List pgsql-hackers
Josh berkus <josh@agliodbs.com> writes:
> On 05/31/2016 10:16 AM, Peter Geoghegan wrote:
>> 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).

> It's still WAY simpler to understand "max_parallel is the number of
> parallel workers I requested".

> Any system where you set it to 2 and get only 1 worker on an idle system
> is going to cause endless queries on the mailing lists.

I really think that a GUC named "max_parallel_workers", which in fact
limits the number of workers and not something else, is the way to go.
        regards, tom lane



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