Re: Make COPY format extendable: Extract COPY TO format implementations

Michael Paquier <michael@paquier.xyz>

From: Michael Paquier <michael@paquier.xyz>
To: Sutou Kouhei <kou@clear-code.com>
Cc: sawada.mshk@gmail.com, zhjwpku@gmail.com, andrew@dunslane.net, nathandbossart@gmail.com, pgsql-hackers@postgresql.org
Date: 2024-02-01T21:51:02Z
Lists: pgsql-hackers
On Fri, Feb 02, 2024 at 12:19:51AM +0900, Sutou Kouhei wrote:
> Here are some numbers on my local machine (Note that my
> local machine isn't suitable for benchmark as I said
> before. Each number is median of "\watch 15" results):
>>
> I'll measure again on my local machine later. I'll stop
> other processes such as Web browser, editor and so on as
> much as possible when I do.

Thanks for compiling some numbers.  This is showing a lot of variance.
Expecially, these two lines in table 2 are showing surprising results
for v7:
  direction     format  n_columns     master         v7        v10
       from        csv          1    917.973   1695.401    871.991
       from     binary          1    841.104   1422.012    820.786

I am going to try to plug in some rusage() calls in the backend for
the COPY paths.  I hope that gives more precision about the backend
activity.  I'll post that with more numbers.
--
Michael

Commits

  1. Refactor Copy{From|To}GetRoutine() to use pass-by-reference argument.

  2. Refactor COPY FROM to use format callback functions.

  3. Refactor COPY TO to use format callback functions.

  4. Another try to fix BF failure introduced in commit ddd5f4f54a.

  5. Revert "Refactor CopyReadAttributes{CSV,Text}() to use a callback in COPY FROM"

  6. Improve COPY TO performance when server and client encodings match

  7. Simplify signature of CopyAttributeOutCSV() in copyto.c

  8. Revert "Refactor CopyAttributeOut{CSV,Text}() to use a callback in COPY TO"

  9. Refactor CopyAttributeOut{CSV,Text}() to use a callback in COPY TO

  10. Refactor CopyReadAttributes{CSV,Text}() to use a callback in COPY FROM

  11. Add progress reporting of skipped tuples during COPY FROM.

  12. pgbench: Add \syncpipeline

  13. meson: Make gzip and tar optional

  14. Export the external file reader used in COPY FROM as APIs.