From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: Tomas Vondra <tomas.vondra@2ndquadrant.com>,
        "Todd A. Cook" <tcook@blackducksoftware.com>,
        Thomas Munro <thomas.munro@enterprisedb.com>,
        PostgreSQL Bugs <pgsql-bugs@postgresql.org>
Subject: Re: BUG #14932: SELECT DISTINCT val FROM table gets stuck in an
 infinite loop
In-reply-to: <20180126234537.dyu6jwnqz7snpq7n@alap3.anarazel.de>
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Comments: In-reply-to Andres Freund <andres@anarazel.de>
	message dated "Fri, 26 Jan 2018 15:45:37 -0800"
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Date: Fri, 26 Jan 2018 18:48:35 -0500
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Andres Freund <andres@anarazel.de> writes:
> On 2017-12-10 23:09:42 +0100, Tomas Vondra wrote:
>> FWIW I do agree the data sets shared in this thread are pretty extreme
>> and it doesn't make much sense to slow the regular cases. I'll be
>> perfectly happy if we stop the OOM, making those cases fast is a bonus.

> Yea, agreed on that. I'm kinda inclined to go for stop-growing in 10,
> and so something better in 11. And then later possibly backpatch if
> we've grown some confidence?

+1.  I'd like to see some response to this included in 10.2, and time
grows short for that.

			regards, tom lane