Re: CREATE DATABASE ... STRATEGY WAL_LOG issues - Mailing list pgsql-hackers

From Andres Freund
Subject Re: CREATE DATABASE ... STRATEGY WAL_LOG issues
Date
Msg-id 20230322051158.mkmq24uttohh6prg@awork3.anarazel.de
Whole thread Raw
In response to Re: CREATE DATABASE ... STRATEGY WAL_LOG issues  (Andres Freund <andres@anarazel.de>)
Responses Re: CREATE DATABASE ... STRATEGY WAL_LOG issues
List pgsql-hackers
Hi,

On 2023-03-21 09:34:14 -0700, Andres Freund wrote:
> On 2023-03-21 11:33:59 -0400, Robert Haas wrote:
> > That feels like it would be slightly more rational behavior,
> > but I'm not smart enough to guess whether anyone would actually be
> > happier (or less happy) after such a change than they are now.
> 
> Yea, I'm not either. The current behaviour does have the feature that it will
> read in some data for each table, but limits trashing of shared buffers for
> huge tables. That's good if your small to medium sized source database isn't
> in s_b, because the next CREATE DATABASE has a change to not need to read the
> data again. But if you have a source database with lots of small relations, it
> can easily lead to swamping s_b.

Patch with the two minimal fixes attached. As we don't know whether it's worth
changing the strategy, the more minimal fixes seem more appropriate.

Greetings,

Andres Freund

Attachment

pgsql-hackers by date:

Previous
From: Peter Smith
Date:
Subject: Re: Data is copied twice when specifying both child and parent table in publication
Next
From: Amit Kapila
Date:
Subject: Re: Initial Schema Sync for Logical Replication