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Re: Rename max_parallel_degree?

Robert Haas <robertmhaas@gmail.com>

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From: Robert Haas <robertmhaas@gmail.com>
To: Julien Rouhaud <julien.rouhaud@dalibo.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Josh Berkus <josh@agliodbs.com>, "David G. Johnston" <david.g.johnston@gmail.com>, Amit Kapila <amit.kapila16@gmail.com>, Peter Geoghegan <pg@heroku.com>, Noah Misch <noah@leadboat.com>, David Rowley <david.rowley@2ndquadrant.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Magnus Hagander <magnus@hagander.net>, Bruce Momjian <bruce@momjian.us>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2016-06-13T01:16:44Z
Lists: pgsql-hackers 
On Sat, Jun 11, 2016 at 6:24 PM, Julien Rouhaud
<julien.rouhaud@dalibo.com> wrote:
> On 11/06/2016 23:37, Julien Rouhaud wrote:
>> On 09/06/2016 16:04, Robert Haas wrote:
>>> OK, I pushed this after re-reviewing it and fixing a number of
>>> oversights.  There remains only the task of adding max_parallel_degree
>>> as a system-wide limit (as opposed to max_parallel_degree now
>>> max_parallel_workers_per_gather which is a per-Gather limit), which
>>> I'm going to argue should be a new open item and not necessarily one
>>> that I have to own myself.  I would like to take care of it, but I
>>> will not put it ahead of fixing actual defects and I will not promise
>>> to have it done in time for 9.6.
>>>
>>
>> PFA a patch to fix this open item.  I used the GUC name provided in the
>> 9.6 open item page (max_parallel_workers), with a default value of 4.
>> Value 0 is another way to disable parallel query.
>>
>
> Sorry I just realized I made a stupid mistake, I didn't check in all
> slots to get the number of active parallel workers. Fixed in attached v2.

I think instead of adding a "bool parallel" argument to
RegisterDynamicBackgroundWorker, we should just define a new constant
for bgw_flags, say BGW_IS_PARALLEL_WORKER.

-- 
Robert Haas
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