Date: Tue, 10 Dec 2019 19:36:06 +0100
From: Tomas Vondra <tomas.vondra@2ndquadrant.com>
To: Alvaro Herrera <alvherre@2ndquadrant.com>
Cc: Thomas Munro <thomas.munro@gmail.com>,
	Andres Freund <andres@anarazel.de>,
	James Coleman <jtc331@gmail.com>,
	PostgreSQL mailing lists <pgsql-bugs@lists.postgresql.org>
Subject: Re: BUG #16104: Invalid DSA Memory Alloc Request in Parallel Hash
Message-ID: <20191210183606.t26c5ypa7bmij3ph@development>
References: <20191210173224.y5vaam6ep7pjmddt@development>
 <20191210173516.GA10987@alvherre.pgsql>
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On Tue, Dec 10, 2019 at 02:35:16PM -0300, Alvaro Herrera wrote:
>On 2019-Dec-10, Tomas Vondra wrote:
>
>> It's probably still a good idea to do this, although I wonder if we
>> might start doing this only when actually running out of bits (and use
>> the current algorithm by default). But I have no idea if that would be
>> any cheaper, and it would add complexity.
>
>I'm under the impression that this patch is proposed for backpatching,
>and that in master we can simply increase the hash width.
>

Possibly, although AFAIK we don't have that patch yet, and I don't
recall any measurements (so it might have overhead too, not sure). But
it's true additional complexity might complicate backpatching.

regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services