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: "Tsunakawa, Takayuki" <tsunakawa.takay@jp.fujitsu.com>, "'David Rowley'" <david.rowley@2ndquadrant.com>, "Imai, Yoshikazu" <imai.yoshikazu@jp.fujitsu.com>
Cc: Alvaro Herrera <alvherre@2ndquadrant.com>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2019-02-08T02:39:36Z
Lists: pgsql-hackers 
Tsunakawa-san,

On 2019/02/08 10:50, Tsunakawa, Takayuki wrote:
> From: David Rowley [mailto:david.rowley@2ndquadrant.com]
>> It's good to see work being done to try and improve this, but I think
>> it's best to do it on another thread. I think there was some agreement
>> upthread about this not being Amit's patch's problem. Doing it here
>> will make keeping track of this more complex than it needs to be.
>> There's also Amit's issue of keeping his patch series up to date. The
>> CFbot is really useful to alert patch authors when that's required,
>> but having other patches posted to the same thread can cause the CFbot
>> to check the wrong patch.
> 
> OK, you're right.  I'll continue this on another thread.

Thank you.  I do appreciate that Imai-san has persistently tried to find
interesting problems to solve beyond the patches we're working on here.
Maybe I chose the the subject line of this thread poorly when I began
working on it.  It should perhaps have been something like "speeding up
planning of point-lookup queries with many partitions" or something like
that.  There are important use cases beyond point lookup even with
partitioned tables (or maybe more so with partitioned tables), but perhaps
unsurprisingly, the bottlenecks in those cases are not *just* in the planner.

Thanks,
Amit

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.