Horton

Re: speeding up planning with partitions

Amit Langote <langote_amit_f8@lab.ntt.co.jp>

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From: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
To: "Imai, Yoshikazu" <imai.yoshikazu@jp.fujitsu.com>, "'Amit Langote'" <amitlangote09@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, David Rowley <david.rowley@2ndquadrant.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Robert Haas <robertmhaas@gmail.com>, Justin Pryzby <pryzby@telsasoft.com>, Pg Hackers <pgsql-hackers@postgresql.org>, Jesper Pedersen <jesper.pedersen@redhat.com>
Date: 2019-03-20T02:33:40Z
Lists: pgsql-hackers 
Imai-san,

On 2019/03/20 11:21, Imai, Yoshikazu wrote:
> (4)
> We expect the performance does not depend on the number of partitions after applying all patches, if possible.
> 
> num of part    TPS
> -----------  -----
> 1024         7,257 (7274, 7246, 7252)
> 2048         6,718 (6627, 6780, 6747)
> 4096         6,472 (6434, 6565, 6416) (quoted from above (3)'s results)
> 8192         6,008 (6018, 5999, 6007)
> 
> It seems the performance still depend on the number of partitions. At the moment, I don't have any idea what cause this problem but can we improve this more?

I've noticed [1] this kind of degradation when the server is built with
Asserts enabled.  Did you?

Thanks,
Amit

[1]
https://www.postgresql.org/message-id/a49372b6-c044-4ac8-84ea-90ad18b1770d%40lab.ntt.co.jp

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.