Re: Choosing parallel_degree - Mailing list pgsql-hackers

From Julien Rouhaud
Subject Re: Choosing parallel_degree
Date
Msg-id 56EA9567.5090801@dalibo.com
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In response to Re: Choosing parallel_degree  (David Rowley <david.rowley@2ndquadrant.com>)
Responses Re: Choosing parallel_degree
List pgsql-hackers
On 17/03/2016 12:21, David Rowley wrote:
> On 18 March 2016 at 00:13, Julien Rouhaud <julien.rouhaud@dalibo.com> wrote:
>> With the current threshold, you need a table bigger than 8 MB to be able
>> to force parallel workers. I'm not sure there'll be benefits for
>> multiple workers on a table smaller than 8 MB, since setting up all the
>> parallel stuff takes time.
> 
> It would be really nice if it were possible to drop the setting really
> low, so that combined with a low parallel_setup_cost we could enable
> parallel query on small tables in the regression test suite.
> 
> 

Indeed. That could also be a use case for moving parallel_threshold to a
GUC, but not sure what'd be best.

-- 
Julien Rouhaud
http://dalibo.com - http://dalibo.org



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