Re: [HACKERS] why not parallel seq scan for slow functions - Mailing list pgsql-hackers

From Michael Paquier
Subject Re: [HACKERS] why not parallel seq scan for slow functions
Date
Msg-id CAB7nPqSw6CNQMiN0ohiqck7syGnJpz61bk-=nbFf71mCdpwyDA@mail.gmail.com
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In response to Re: [HACKERS] why not parallel seq scan for slow functions  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: [HACKERS] why not parallel seq scan for slow functions  (Marina Polyakova <m.polyakova@postgrespro.ru>)
List pgsql-hackers
On Fri, Nov 10, 2017 at 4:42 AM, Robert Haas <robertmhaas@gmail.com> wrote:
> On Thu, Nov 9, 2017 at 3:47 AM, Amit Kapila <amit.kapila16@gmail.com> wrote:
>> I think I understood your concern after some offlist discussion and it
>> is primarily due to the inheritance related check which can skip the
>> generation of gather paths when it shouldn't.  So what might fit
>> better here is a straight check on the number of base rels such that
>> allow generating gather path in set_rel_pathlist, if there are
>> multiple baserels involved.  I have used all_baserels which I think
>> will work better for this purpose.
>
> Yes, that looks a lot more likely to be correct.
>
> Let's see what Tom thinks.

Moved to next CF for extra reviews.
-- 
Michael


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