Date: Fri, 5 Apr 2019 00:06:04 -0300
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Andres Freund <andres@anarazel.de>
Cc: Pavan Deolasee <pavan.deolasee@gmail.com>,
	Masahiko Sawada <sawada.mshk@gmail.com>,
	pgsql-hackers <pgsql-hackers@postgresql.org>,
	Jeff Janes <jeff.janes@gmail.com>,
	Simon Riggs <simon@2ndquadrant.com>,
	Tomas Vondra <tomas.vondra@2ndquadrant.com>
Subject: Re: COPY FREEZE and setting PD_ALL_VISIBLE/visibility map bits
Message-ID: <20190405030604.GA3360@alvherre.pgsql>
MIME-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <20190404214520.7rfufsubxekodypr@alap3.anarazel.de>
User-Agent: Mutt/1.9.4 (2018-02-28)
Precedence: bulk

On 2019-Apr-04, Andres Freund wrote:

> On 2019-04-04 12:23:08 -0700, Andres Freund wrote:
> > Also, how is this code even close to correct?
> > CheckAndSetPageAllVisible() modifies the buffer in a crucial way, and
> > there's no WAL logging? Without even a comment arguing why that's OK (I
> > don't think it is)?
> 
> Peter Geoghegan just reminded me over IM that there's actually logging
> inside log_heap_visible(), called from visibilitymap_set(). Still lacks
> a critical section though.

Hmm, isn't there already a critical section in visibilitymap_set itself?

> I still think this is the wrong architecture.

Hmm.

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