From: Tom Lane <tgl@sss.pgh.pa.us>
To: Tomas Vondra <tomas.vondra@enterprisedb.com>
cc: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>,
        "houzj.fnst@fujitsu.com" <houzj.fnst@fujitsu.com>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Fdw batch insert error out when set batch_size > 65535
In-reply-to: <1271666.1623218746@sss.pgh.pa.us>
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Comments: In-reply-to Tom Lane <tgl@sss.pgh.pa.us>
	message dated "Wed, 09 Jun 2021 02:05:46 -0400"
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Date: Wed, 09 Jun 2021 02:28:29 -0400
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 <https://www.postgresql.org/message-id/1272762.1623220109%40sss.pgh.pa.us>
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I wrote:
> Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com> writes:
>>> I've added a simple regression test to postgres_fdw, testing that batch
>>> sizes > 65535 work fine, and pushed the fix.

>> I was earlier thinking of adding one, but stopped because it might
>> increase the regression test execution time. It looks like that's true
>> - with and without the test case it takes 17 sec and 4 sec
>> respectively on my dev system which is 4X slower. I'm not sure if this
>> is okay.

> The cost, versus the odds of ever detecting a problem, doesn't
> seem like a good tradeoff.

I took a quick look and noted that on buildfarm member longfin
(to take a random example that's sitting a few feet from me),
the time for contrib-install-check went from 34 seconds before
this patch to 40 seconds after.  I find that completely
unacceptable compared to the likely value of this test case.

			regards, tom lane