Re: Making pg_rewind faster

Alexander Korotkov <aekorotkov@gmail.com>

From: Alexander Korotkov <aekorotkov@gmail.com>

To: Justin Kwan <justinpkwan@outlook.com>

Cc: Tom Lane <tgl@sss.pgh.pa.us>, Michael Paquier <michael@paquier.xyz>, pgsql-hackers <pgsql-hackers@postgresql.org>, vignesh <vignesh@cloudflare.com>, vignesh ravichandran <admin@viggy28.dev>, "hlinnaka@iki.fi" <hlinnaka@iki.fi>, "jkwan@cloudflare.com" <jkwan@cloudflare.com>

Date: 2022-09-13T17:50:20Z

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 →

pg_rewind: Skip copy of WAL segments generated before point of divergence
- 5173bfd0443e 19 (unreleased) landed
pg_rewind: Extend code detecting relation files to work with WAL files
- 6ae08d9583e9 19 (unreleased) landed
Split TESTDIR into TESTLOGDIR and TESTDATADIR
- c47885bd8b69 16.0 cited

Hi, Justin!

On Fri, Jul 29, 2022 at 1:05 PM Justin Kwan <justinpkwan@outlook.com> wrote:
> Not sure if this email went through previously but thank you for your feedback, I've incorporated your suggestions by scanning the logs produced from pg_rewind when asserting that certain WAL segment files were skipped from being copied over to the target server.
>
> I've also updated the pg_rewind patch file to target the Postgres master branch (version 16 to be). Please see attached.

Thank you for the revision.

I've taken a look at this patch. Overall it looks good to me. I also
don't see any design objections in the thread.

A couple of points from me:
1) I would prefer to evade hard-coded names for WAL segments in the
tap tests. Could we calculate the names in the tap tests based on the
diverge point, etc.?
2) Patch contains some indentation with spaces, which should be done
in tabs. Please consider either manually fixing this or running
pgindent over modified files.

------
Regards,
Alexander Korotkov