Date: Tue, 3 Sep 2019 12:36:33 -0400
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Cc: Melanie Plageman <melanieplageman@gmail.com>,
	Hubert Zhang <hzhang@pivotal.io>,
	hackers <pgsql-hackers@postgresql.org>,
	Thomas Munro <thomas.munro@gmail.com>
Subject: Re: accounting for memory used for BufFile during hash joins
Message-ID: <20190903163633.GA16230@alvherre.pgsql>
MIME-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <20190711154011.lmkp7jyd3e2zfcnx@development>
User-Agent: Mutt/1.9.4 (2018-02-28)
Precedence: bulk

On 2019-Jul-11, Tomas Vondra wrote:

> On Wed, Jul 10, 2019 at 04:51:02PM -0700, Melanie Plageman wrote:

> > I think implementing support for parallel hashjoin or explicitly
> > disabling it would be the bare minimum for this patch, which is why I
> > made 2 its own item. I've marked it as returned to author for this
> > reason.
> 
> OK. I'm a bit confused / unsure what exactly our solution to the various
> hashjoin issues is. I have not been paying attention to all the various
> threads, but I thought we kinda pivoted to the BNL approach, no? I'm not
> against pushing this patch (the slicing one) forward and then maybe add
> BNL on top.

So what's a good way forward for this patch?  Stalling forever like a
glacier is not an option; it'll probably end up melting.  There's a lot
of discussion on this thread which I haven't read, and it's not
immediately clear to me whether this patch should just be thrown away in
favor of something completely different, or it can be considered a first
step in a long road.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services