Re: Rename max_parallel_degree?

On Fri, Jun 3, 2016 at 9:39 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>> I think we should just go with max_parallel_workers for a limit on
>> total parallel workers within max_work_processes, and
>> max_parallel_workers_per_gather for a per-Gather limit. It's slightly
>> annoying that we may end up renaming the latter GUC, but not as
>> annoying as spending another three weeks debating this and missing
>> beta2.
>
> +1. I'm not as convinced as you are that we'll replace the GUC later,
> but in any case this is an accurate description of the current
> semantics. And I'm really *not* in favor of fudging the name with
> the intent of changing the GUC's semantics later --- that would fail
> all sorts of compatibility expectations.

Here's a patch change max_parallel_degree to
max_parallel_workers_per_gather, and also changing parallel_degree to
parallel_workers. I haven't tackled adding a separate
max_parallel_workers, at least not yet. Are people OK with this?

Note that there is a dump/restore hazard if people have set the
parallel_degree reloption on a beta1 install, or used ALTER { USER |
DATABASE } .. SET parallel_degree. Can everybody live with that?
Should I bump catversion when applying this?

--
Robert Haas
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