Re: [HACKERS] Parallel tuplesort (for parallel B-Tree index creation)

On Fri, Jan 26, 2018 at 2:04 PM, Peter Geoghegan <pg(at)bowt(dot)ie> wrote:
> On Fri, Jan 26, 2018 at 10:33 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> I'm busy with other things, so no rush.
>
> Got it.
>
> There is one question that I should probably get clarity on ahead of
> the next revision, which is: Should I rip out the code that disallows
> a "degenerate parallel CREATE INDEX" when
> parallel_leader_participation=off, or should I instead rip out any
> code that deals with parallel_leader_participation, and always have
> the leader participate as a worker?
>
> If I did the latter, then leader non-participation would live on as a
> #define debug option within nbtsort.c. It definitely seems like we'd
> want to preserve that at a minimum.

Hmm, I like the idea of making it a #define instead of having it
depend on parallel_leader_participation. Let's do that. If the
consensus is later that it was the wrong decision, it'll be easy to
change it back.

--
Robert Haas
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