Message-ID: <e22b9d56e56d4cecd2cc7e95a9758e09cc187c8f.camel@j-davis.com>
Subject: Re: Proposal: "query_work_mem" GUC, to distribute working memory to
 the query's individual operators
From: Jeff Davis <pgsql@j-davis.com>
To: James Hunter <james.hunter.pg@gmail.com>
Cc: "pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>
Date: Tue, 11 Feb 2025 10:00:14 -0800
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On Mon, 2025-02-10 at 19:09 -0800, James Hunter wrote:
> I think it makes sense to split the work into two parts: one part
> that
> improves SQL execution, and a second part that improves the
> optimizer,
> to reflect the improvements to execution.

I like the idea to store the value of work_mem in the
path/plan/executor nodes, and use that at execution time rather than
the GUC directly.

IIUC, that would allow an extension to do what you want, right? A
planner hook could just walk the tree and edit those values for
individual nodes, and the executor would enforce them.

Regards,
	Jeff Davis