Re: speeding up planning with partitions

Justin Pryzby <pryzby@telsasoft.com>

From: Justin Pryzby <pryzby@telsasoft.com>
To: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, David Rowley <david.rowley@2ndquadrant.com>, "Imai, Yoshikazu" <imai.yoshikazu@jp.fujitsu.com>, Amit Langote <amitlangote09@gmail.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2019-02-22T16:59:32Z
Lists: pgsql-hackers
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.

with patch:
    173 pread64
     76 lseek
     47 open
     38 brk

without patch:
   1276 lseek
    693 pread64
    647 open
    594 brk

> +		if (IS_SIMPLE_REL(rel1) && child_rel1 == NULL)
> +			child_rel1 = build_dummy_partition_rel(root, rel1, baserel1,
> +												   cnt_parts);
> +		if (IS_SIMPLE_REL(rel1) && child_rel2 == NULL)
> +			child_rel2 = build_dummy_partition_rel(root, rel2, baserel2,
> +												   cnt_parts);

Should 2nd "if" say IS_SIMPLE_REL(rel2) ?

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.