Re: assessing parallel-safety

Thom Brown wrote:
> On 18 March 2015 at 16:01, Robert Haas <robertmhaas@gmail.com> wrote:
> > On Tue, Mar 17, 2015 at 9:48 AM, Robert Haas <robertmhaas@gmail.com> wrote:
> >> On Tue, Mar 17, 2015 at 2:26 AM, Noah Misch <noah@leadboat.com> wrote:
> >>> Neither that rule, nor its variant downthread, would hurt operator authors too
> >>> much.  To make the planner categorically parallel-safe, though, means limiting
> >>> evaluate_function() to parallel-safe functions.  That would dramatically slow
> >>> selected queries.  It's enough for the PL scenario if planning a parallel-safe
> >>> query is itself parallel-safe.  If the planner is parallel-unsafe when
> >>> planning a parallel-unsafe query, what would suffer?
> >>
> >> Good point.  So I guess the rule can be that planning a parallel-safe
> >> query should be parallel-safe.  From there, it follows that estimators
> >> for a parallel-safe operator must also be parallel-safe.  Which seems
> >> fine.
> >
> > More work is needed here, but for now, here is a rebased patch, per
> > Amit's request.
> 
> This no longer applies due to changes in commit
> 13dbc7a824b3f905904cab51840d37f31a07a9ef.

You should be able to drop the pg_proc.h changes and run the supplied
perl program.  (I'm not sure that sending the patched pg_proc.h together
with this patch is all that useful, really.)

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
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