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Date: Mon, 30 Aug 2021 09:44:43 +0200
From: hubert depesz lubaczewski <depesz@depesz.com>
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To: Tom Lane <tgl@sss.pgh.pa.us>
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Subject: Re: Can we get rid of repeated queries from pg_dump?
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On Fri, Aug 27, 2021 at 05:23:23PM -0400, Tom Lane wrote:
> I experimented with the attached, very quick-n-dirty patch to collect
> format_type results during the initial scan of pg_type, instead.  On the
> regression database in HEAD, it reduces the number of queries pg_dump
> issues from 3260 to 2905; but I'm having a hard time detecting any net
> performance change.

Hi,
So, I applied it to brand new HEAD from git, Result: