Re: [PATCH] pg_dump: lock tables in batches

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>

To: Aleksander Alekseev <aleksander@timescale.com>

Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>

Date: 2022-12-07T15:44:33Z

Lists: pgsql-hackers

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During pg_dump startup, acquire table locks in batches.
- 5f53b42cfd05 16.0 landed

Aleksander Alekseev <aleksander@timescale.com> writes:
> What he proposes is taking the locks in batches.

I have a strong sense of deja vu here.  I'm pretty sure I experimented
with this idea last year and gave up on it.  I don't recall exactly
why, but either it didn't show any meaningful performance improvement
for me or there was some actual downside (that I'm not remembering
right now).

This would've been in the leadup to 989596152 and adjacent commits.
I took a quick look through the threads cited in those commit messages
and didn't find anything about it, but I think the discussion had
gotten scattered across more threads.  Some digging in the archives
could be useful.

			regards, tom lane