Date: Fri, 15 Feb 2019 20:53:51 -0800
From: Andres Freund <andres@anarazel.de>
To: Hubert Zhang <hzhang@pivotal.io>
Cc: Michael Paquier <michael@paquier.xyz>,
	Robert Haas <robertmhaas@gmail.com>,
	"pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>,
	Tomas Vondra <tomas.vondra@2ndquadrant.com>,
	Heikki Linnakangas <hlinnakangas@pivotal.io>
Subject: Re: Control your disk usage in PG: Introduction to Disk Quota
 Extension
Message-ID: <20190216045351.q344ex2utwk7ndtr@alap3.anarazel.de>
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Hi,


On 2019-01-30 10:26:52 +0800, Hubert Zhang wrote:
> Hi Michael, Robert
> For you question about the hook position, I want to explain more about the
> background why we want to introduce these hooks.
> We wrote a diskquota extension <https://github.com/greenplum-db/diskquota>
> [ ...]
> On Tue, Jan 22, 2019 at 12:08 PM Hubert Zhang <hzhang@pivotal.io> wrote:
> 
> > > For this particular purpose, I don't immediately see why you need a
> >> > hook in both places.  If ReadBuffer is called with P_NEW, aren't we
> >> > guaranteed to end up in smgrextend()?
> >> Yes, that's a bit awkward.

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Greetings,

Andres Freund