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Re: parallel joins, and better parallel explain - Mailing list pgsql-hackers

From Amit Kapila
Subject Re: parallel joins, and better parallel explain
Date
Msg-id CAA4eK1KURNE0oEs9R6-yUnLieo4FFDvirc=zfju1xfLSs8uwZw@mail.gmail.com
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In response to Re: parallel joins, and better parallel explain  (Amit Kapila <amit.kapila16@gmail.com>)
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On Tue, Dec 1, 2015 at 5:51 PM, Amit Kapila <amit.kapila16@gmail.com> wrote:
>
> On Thu, Nov 26, 2015 at 8:11 AM, Robert Haas <robertmhaas@gmail.com> wrote:
> >
> > Attached find a patch that does (mostly) two things.
> >
>
> I have started looking into this and would like to share few findings
> with you:
>
>
> - There seems to be some inconsistency in Explain's output when
> multiple workers are used.
>

Forgot to mention that I have changed code of cost_seqscan() by adding
below line, so that it can select parallel plan.  This is just a temporary
change to verify Explain's output.

cost_seqscan()
{
..

run_cost = run_cost / (path->parallel_degree + 0.5);

..
}

With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com

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