On Sun, May 13, 2018 at 04:40:19PM +0530, Amit Kapila wrote:
> On Fri, May 11, 2018 at 8:38 PM, Bruce Momjian <bruce@momjian.us> wrote:
> > I have committed the first draft of the Postgres 11 release notes. I
> > will add more markup soon. You can view the most current version here:
> >
> > http://momjian.us/pgsql_docs/release-11.html
> >
> > I expect a torrent of feedback. ;-)
> >
>
> Thanks for compiling the first draft. I think there are few things
> which we should add to the Parallel Queries section. (a) commit
> e89a71fb449af2ef74f47be1175f99956cf21524 -
> Pass InitPlan values to workers via Gather (Merge). We can write
> something like "Allow the part of the plan that references an initplan
> to run in parallel" or "Parallelise queries containing initplans",
Uh, I need some explaination of what an initplan is and what type of
query this helps.
> (b) "Parallelise queries that contains expensive functions in target
> lists" (Commits - 3f90ec8597c3515e0d3190613b31491686027e4b and
> 11cf92f6e2e13c0a6e3f98be3e629e6bd90b74d5).
So we generate the entire query before the target list function calls,
the run another parallel run just for those function calls? Really? Do
we run each column in its own worker or do we split the result set into
parts and run those in parallel? How do we know, just the function call
costs? I can admit I never saw that coming.
--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://enterprisedb.com
+ As you are, so once was I. As I am, so you will be. +
+ Ancient Roman grave inscription +
