From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: Amit Kapila <amit.kapila16@gmail.com>,
        Tomas Vondra <tomas.vondra@enterprisedb.com>,
        pgsql-hackers@lists.postgresql.org
Subject: Re: Stabilizing the test_decoding checks, take N
In-reply-to: <20220417215203.2wjhsjszxh4htyby@alap3.anarazel.de>
References: <1958043.1650129119@sss.pgh.pa.us>
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Comments: In-reply-to Andres Freund <andres@anarazel.de>
	message dated "Sun, 17 Apr 2022 14:52:03 -0700"
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Date: Sun, 17 Apr 2022 17:55:43 -0400
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Andres Freund <andres@anarazel.de> writes:
> On 2022-04-17 12:01:53 -0400, Tom Lane wrote:
>> It seems likely to me that trying to make a test like this one blind to
>> autovacuum/autoanalyze activity will make it less useful, not more so.
>> Why is such blindness desirable?

> Maybe I misunderstood - I thought you were proposing to prevent
> autovacuum by increasing naptime? Won't that precisely blind us to
> autovacuum/analyze?  Hiding empty xacts happens "very late", so all the
> decoding etc still happens.

My concern is basically that if we hack the code so it does not report
autovacuum activity, that might result in it also not reporting other
things that are more interesting.  So I think an external method of
suppressing test noise due to autovac is more advisable.

			regards, tom lane