From: Tom Lane <tgl@sss.pgh.pa.us>
To: Amit Kapila <amit.kapila16@gmail.com>
cc: Thomas Munro <thomas.munro@enterprisedb.com>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
        hlinnaka <hlinnaka@iki.fi>
Subject: Re: SerializeParamList vs machines with strict alignment
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Comments: In-reply-to Amit Kapila <amit.kapila16@gmail.com>
	message dated "Tue, 02 Oct 2018 06:56:45 +0530"
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Date: Mon, 01 Oct 2018 21:38:53 -0400
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Amit Kapila <amit.kapila16@gmail.com> writes:
> I think if we do Analyze on the table after populating rows, it should
> use just one worker and that should be sufficient to hit the case
> being discussed.  I would like to change the test so that it uses just
> one worker.

I thought that adding an ANALYZE would make the test be net slower, not
faster; ANALYZE isn't free, even on just a row or so.  Also, I believe
that coding the test this way makes the leader send the param values to
multiple workers, which would flush out any problems with serializing a
value multiple times.  As against that, there's a hazard that the number
of workers might not be stable ... but it seems like we have lots of
other occurrences of that same hazard elsewhere in this test script.

			regards, tom lane