Re: [HACKERS] Parallel Plans and Cost of non-filter functions - Mailing list pgsql-hackers

From Amit Kapila
Subject Re: [HACKERS] Parallel Plans and Cost of non-filter functions
Date
Msg-id CAA4eK1JmGtnF7Q4O-V3Ya9-nPwXb=Opmcp0V74BXP9EW3nHBNA@mail.gmail.com
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In response to Re: [HACKERS] Parallel Plans and Cost of non-filter functions  (Paul Ramsey <pramsey@cleverelephant.ca>)
List pgsql-hackers
On Mon, Nov 6, 2017 at 7:40 PM, Paul Ramsey <pramsey@cleverelephant.ca> wrote:
> From my perspective, this is much much better. For sufficiently large
> tables, I get parallel behaviour without jimmying with the defaults on
> parallel_setup_cost and parallel_tuple_cost. *And*, the parallel behaviour
> *is* sensitive to the costs of functions in target lists, so reasonably
> chosen costs will flip us into a parallel mode for expensive functions
> against smaller tables too.
>

Thanks for the confirmation.

> Hopefully some variant of this finds it's way into core! Is there any way I
> can productively help?

You have already helped a lot by providing the use case, but feel free
to ping on that thread if you find it is not moving.

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


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