Horton

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

Michael Paquier <michael@paquier.xyz>

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From: Michael Paquier <michael@paquier.xyz>
To: Sutou Kouhei <kou@clear-code.com>
Cc: andres@anarazel.de, sawada.mshk@gmail.com, zhjwpku@gmail.com, andrew@dunslane.net, nathandbossart@gmail.com, pgsql-hackers@postgresql.org
Date: 2024-03-01T05:31:38Z
Lists: pgsql-hackers 
On Thu, Feb 22, 2024 at 06:39:48PM +0900, Sutou Kouhei wrote:
> If so, adding the change independently on HEAD makes
> sense. But I don't know why that improves
> performance... Inlining?

I guess so.  It does not make much of a difference, though.  The thing
is that the dispatch caused by the custom callbacks called for each
row is noticeable in any profiles I'm taking (not that much in the
worst-case scenarios, still a few percents), meaning that this impacts
the performance for all the in-core formats (text, csv, binary) as
long as we refactor text/csv/binary to use the routines of copyapi.h.
I don't really see a way forward, except if we don't dispatch the
in-core formats to not impact the default cases.  That makes the code
a bit less elegant, but equally efficient for the existing formats.
--
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.