Re: Parallel Seq Scan

On Thu, Nov 5, 2015 at 10:49 PM, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
> On Thu, Nov 5, 2015 at 11:54 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> I was thinking about this idea:
>>
>> 1. Add a parallel_aware flag to each plan.
>
> Okay, so shall we add it in generic Plan node or to specific plan nodes
> like SeqScan, IndexScan, etc. To me, it appears that parallelism is
> a node specific property, so we should add it to specific nodes and
> for now as we are parallelising seq scan, so we can add this flag in
> SeqScan node. What do you say?

I think it should go in the Plan node itself. Parallel Append is
going to need a way to test whether a node is parallel-aware, and
there's nothing simpler than if (plan->parallel_aware). That makes
life simple for EXPLAIN, too.

--
Robert Haas
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