Horton

Re: [HACKERS] [PATCH] Incremental sort

Tomas Vondra <tomas.vondra@2ndquadrant.com>

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From: Tomas Vondra <tomas.vondra@2ndquadrant.com>
To: Alexander Korotkov <a.korotkov@postgrespro.ru>, jtc331@gmail.com
Cc: David Steele <david@pgmasters.net>, Tom Lane <tgl@sss.pgh.pa.us>, Teodor Sigaev <teodor@sigaev.ru>, Alvaro Herrera <alvherre@alvh.no-ip.org>, Darafei Praliaskouski <me@komzpa.net>, Antonin Houska <ah@cybertec.at>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2018-10-28T18:27:44Z
Lists: pgsql-hackers 
Hi Alexander,

On 06/01/2018 04:22 PM, Alexander Korotkov wrote:
> Hi, James!
> 
> On Thu, May 31, 2018 at 11:10 PM James Coleman <jtc331@gmail.com
> <mailto:jtc331@gmail.com>> wrote:
> 
>     I've attached an updated copy of the patch that applies cleanly to
>     current master.
> 
> 
> Thank you for rebasing this patch.  Next time sending a patch,
> please make sure you've bumped its version, if even you made no
> changes there besides to pure rebase. Otherwise, it would be hard to
> distinguish patch versions, because patch files have exactly same
> names.
> 
> I'd like to note, that I'm going to provide revised version of this 
> patch to the next commitfest. After some conversations at PGCon
> regarding this patch, I got more confident that providing separate
> paths for incremental sorts is right.  In the next revision of this
> patch, incremental sort paths would be provided in more cases.
> 

Do you plan to submit an updated patch version for the November CF? It
would be good to look at the costing model soon, otherwise it might end
up missing PG12, and that would be unfortunate.

regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services

Commits

  1. Further adjustments to Hashagg EXPLAIN ANALYZE output

  2. Rework EXPLAIN format for incremental sort

  3. Fix typos and improve incremental sort comments

  4. Stabilize incremental_sort tests

  5. Minor improvements in Incremental Sort explain

  6. Consider Incremental Sort paths at additional places

  7. Fix representation of SORT_TYPE_STILL_IN_PROGRESS.

  8. Fix failures in incremental_sort due to number of workers

  9. Fix show_incremental_sort_info with force_parallel_mode

  10. Implement Incremental Sort

  11. Fix handling of "Subplans Removed" field in EXPLAIN output.

  12. Fix EXPLAIN (SETTINGS) to follow policy about when to print empty fields.

  13. Ensure plpgsql result tuples have the right composite type marking.

  14. Propagate sort instrumentation from workers back to leader.

  15. Make new regression test case parallel-safe, and improve its output.

  16. Push limit through subqueries to underlying sort, where possible.

  17. Fix inappropriate printing of never-measured times in EXPLAIN.

  18. Fix some infelicities in EXPLAIN output for parallel query plans.