Re: speeding up planning with partitions

Justin Pryzby <pryzby@telsasoft.com>

From: Justin Pryzby <pryzby@telsasoft.com>
To: Amit Langote <amitlangote09@gmail.com>
Cc: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>, Tom Lane <tgl@sss.pgh.pa.us>, David Rowley <david.rowley@2ndquadrant.com>, "Imai, Yoshikazu" <imai.yoshikazu@jp.fujitsu.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2019-02-22T18:01:46Z
Lists: pgsql-hackers
On Sat, Feb 23, 2019 at 02:54:35AM +0900, Amit Langote wrote:
> > On Fri, Feb 22, 2019 at 09:45:38PM +0900, Amit Langote wrote:
> > > I have updated the inheritance expansion patch.
> > >
> > > Patch 0001 rewrites optimizer/utils/inherit.c, so that it allows
> >
> > Thanks for your continued work on this.
> >
> > I applied v23 patch and imported one of our customers' schema, and ran explain
> > on a table with 210 partitions.  With patch applied there are 10x fewer system
> > calls, as intended.
> 
> OK, great.  I guess you were running SELECT?  Just in case you missed,
> the patch to improve UPDATE/DELETE scalability is no longer part of
> this patch series.

Yes, I understand the scope is reduced.

Actually, when I tested last month, I don't think I realized that UPDATE/DELETE
was included.  Otherwise I would've also tested to see if it resolves the
excessive RAM use with many partitions, with the explanation given that query
is being replanned for every partition.

I set target version to v12.
https://commitfest.postgresql.org/22/1778/

Justin


Commits

  1. Clean up handling of constraint_exclusion and enable_partition_pruning.

  2. Add test case exercising formerly-unreached code in inheritance_planner.

  3. Speed up planning when partitions can be pruned at plan time.

  4. Avoid crash in partitionwise join planning under GEQO.

  5. Avoid passing query tlist around separately from root->processed_tlist.

  6. Build "other rels" of appendrel baserels in a separate step.

  7. Get rid of duplicate child RTE for a partitioned table.

  8. Rearrange make_partitionedrel_pruneinfo to avoid work when we can't prune.

  9. Don't copy PartitionBoundInfo in set_relation_partition_info.

  10. Move building of child base quals out into a new function

  11. Reorganize planner code moved in b60c39759908

  12. Move inheritance expansion code into its own file

  13. Fix inherited UPDATE/DELETE with UNION ALL subqueries.

  14. Rearrange planner to save the whole PlannerInfo (subroot) for a subquery.