Horton

Re: [HACKERS] Partition-wise aggregation/grouping

Jeevan Chalke <jeevan.chalke@enterprisedb.com>

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From: Jeevan Chalke <jeevan.chalke@enterprisedb.com>
To: Andres Freund <andres@anarazel.de>
Cc: Robert Haas <robertmhaas@gmail.com>, Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>, Dilip Kumar <dilipbalaut@gmail.com>, David Rowley <david.rowley@2ndquadrant.com>, Rajkumar Raghuwanshi <rajkumar.raghuwanshi@enterprisedb.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2018-03-27T06:18:11Z
Lists: pgsql-hackers 
On Tue, Mar 27, 2018 at 3:33 AM, Andres Freund <andres@anarazel.de> wrote:

> Hi,
>
> On 2018-03-23 17:01:54 +0530, Jeevan Chalke wrote:
> > Attached patch which fixes that.
>
> Thanks, will push. For the future, I'd be more likely to notice if you
> CC me ;)
>

Sure. Thanks.


>
>
> > However, I am not sure whether it is expected to have stable regression
> run
> > with installcheck having local settings.
> > For example, If I have enabale_hashagg = false locally; I will definitely
> > see failures.
> >
> > ISTM, that I am missing Andres point here.
>
> I don't think there's a hard and fast rule here. I personally often
> during development disable parallelism because it makes some things
> harder (you can't easily debug crashes with gdb, benchmarks show larger
> variance, ...).


Yep.


>   There doesn't seem to be an equivalent benefit to
> support running e.g. with enabale_hashagg = false.
>

OK.
Noted.

Thanks for the explanation.


>
> - Andres
>



-- 
Jeevan Chalke
Technical Architect, Product Development
EnterpriseDB Corporation
The Enterprise PostgreSQL Company

Commits

  1. postgres_fdw: Push down partition-wise aggregation.

  2. Remove 'target' from GroupPathExtraData.

  3. Implement partition-wise grouping/aggregation.

  4. Don't pass the grouping target around unnecessarily.

  5. Determine grouping strategies in create_grouping_paths.

  6. Defer creation of partially-grouped relation until it's needed.

  7. Split create_grouping_paths into degenerate and non-degenerate cases.

  8. Pass additional arguments to a couple of grouping-related functions.

  9. Fix logic error in add_paths_to_partial_grouping_rel.

  10. Minor cleanup of code related to partially_grouped_rel.

  11. Add a new upper planner relation for partially-aggregated results.

  12. Charge cpu_tuple_cost * 0.5 for Append and MergeAppend nodes.

  13. Rename enable_partition_wise_join to enable_partitionwise_join

  14. Factor some code out of create_grouping_paths.

  15. Pad XLogReaderState's main_data buffer more aggressively.

  16. Prevent int128 from requiring more than MAXALIGN alignment.

  17. Fix DROP SUBSCRIPTION hang

  18. Inject $(ICU_LIBS) regardless of platform.

  19. Some preliminary refactoring towards partitionwise join.