From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
cc: Nathan Bossart <nathandbossart@gmail.com>, pgsql-hackers@postgresql.org,
        schneider@ardentperf.com
Subject: Re: monitoring usage count distribution
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References: <20230130233040.GA2800702@nathanxps13>
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Comments: In-reply-to Robert Haas <robertmhaas@gmail.com>
	message dated "Tue, 04 Apr 2023 14:31:36 -0400"
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Date: Tue, 04 Apr 2023 14:40:02 -0400
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Robert Haas <robertmhaas@gmail.com> writes:
> On Mon, Jan 30, 2023 at 6:30=E2=80=AFPM Nathan Bossart <nathandbossart@g=
mail.com> wrote:
>> My colleague Jeremy Schneider (CC'd) was recently looking into usage co=
unt
>> distributions for various workloads, and he mentioned that it would be =
nice
>> to have an easy way to do $SUBJECT.

> I'm skeptical that pg_buffercache_summary() is a good idea at all, but
> having it display the average usage count seems like a particularly
> poor idea. That information is almost meaningless. Replacing that with
> a six-element integer array would be a clear improvement and, IMHO,
> better than adding yet another function to the extension.

I had not realized that pg_buffercache_summary() is new in v16,
but since it is, we still have time to rethink its definition.
+1 for de-aggregating --- I agree that the overall average is
unlikely to have much value.

			regards, tom lane