Horton

Re: [PoC] Reducing planning time when tables have many partitions

Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>

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From: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
To: Yuya Watari <watari.yuya@gmail.com>
Cc: Dmitry Dolgov <9erthalion6@gmail.com>, PostgreSQL Developers <pgsql-hackers@lists.postgresql.org>, jian he <jian.universality@gmail.com>, Alena Rybakina <lena.ribackina@yandex.ru>, Andrei Lepikhov <a.lepikhov@postgrespro.ru>, David Rowley <dgrowleyml@gmail.com>, Thom Brown <thom@linux.com>, Alvaro Herrera <alvherre@alvh.no-ip.org>, Zhang Mingli <zmlpostgres@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>
Date: 2024-12-03T04:12:35Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Update wording in optimizer/README for EquivalenceClasses

  2. Speedup child EquivalenceMember lookup in planner

  3. Allow planner to use Merge Append to efficiently implement UNION

  4. Remove trailing zero words from Bitmapsets

  5. Make Vars be outer-join-aware.

  6. Avoid making commutatively-duplicate clauses in EquivalenceClasses.

On Mon, Dec 2, 2024 at 2:22 PM Yuya Watari <watari.yuya@gmail.com> wrote:

>
> 4. Discussion
>
> First of all, tables 1, 2 and the figure attached to this email show
> that likely and unlikely do not have the effect I expected. Rather,
> tables 3, 4, 5 and 6 imply that they can have a negative effect on
> queries A and B. So it is better to remove these likely and unlikely.
>
> For the design change, the benchmark results show that it may cause
> some regression, especially for smaller sizes. However, Figure 1 also
> shows that the regression is much smaller than its variance. This
> design change is intended to improve code maintainability. The
> regression is small enough that I think these results are acceptable.
> What do you think about this?
>
> [1] https://www.postgresql.org/message-id/CAJ2pMkZk-Nr=yCKrGfGLu35gK-D179QPyxaqtJMUkO86y1NmSA@mail.gmail.com
> [2] https://www.postgresql.org/message-id/CAJ2pMkYcKHFBD_OMUSVyhYSQU0-j9T6NZ0pL6pwbZsUCohWc7Q@mail.gmail.com
>

Hi Yuya,
For one of the earlier versions, I had reported a large memory
consumption in all cases and increase in planning time for Assert
enabled builds. How does the latest version perform in those aspects?


-- 
Best Wishes,
Ashutosh Bapat