From: Tom Lane <tgl@sss.pgh.pa.us>
To: "Joel Jacobson" <joel@compiler.org>
cc: "Arseniy Mukhin" <arseniy.mukhin.dev@gmail.com>,
        pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: Optimize LISTEN/NOTIFY
In-reply-to: <def143ea-2425-489e-9699-713f9fccb27f@app.fastmail.com>
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Comments: In-reply-to "Joel Jacobson" <joel@compiler.org>
	message dated "Wed, 15 Oct 2025 23:10:47 +0200"
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Date: Wed, 15 Oct 2025 17:15:15 -0400
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"Joel Jacobson" <joel@compiler.org> writes:
> I assume the separate "advisory" queue position field
> would actually need to be two struct fields, since a queue position
> consists of a page and an offset, right?

No, I'd think you'd have both

    QueuePosition pos;            /* backend has read queue up to here */
    QueuePosition advisory_pos;   /* backend could skip queue to here */

in QueueBackendStatus.  The other seems way too confusing.

			regards, tom lane