Date: Tue, 1 Sep 2020 17:01:31 -0400
From: Bruce Momjian <bruce@momjian.us>
To: Pavel Luzanov <p.luzanov@postgrespro.ru>
Cc: "David G. Johnston" <david.g.johnston@gmail.com>,
	pluzanov@postgrespro.ru, pgsql-docs@lists.postgresql.org
Subject: Re: max_wal_size
Message-ID: <20200901210131.GB13613@momjian.us>
References: <159057129673.7025.17016799863173731176@wrigleys.postgresql.org>
 <CAKFQuwZOwfUwOxNh5KjUjCSFaecUWxtHEbPHEK8CJF1+zn9Bjg@mail.gmail.com>
 <92491c6d07a3216ef2caee8ef55c02b5@postgrespro.ru>
 <CAKFQuwYOGSRbcWnSEo7vp7JJktdH9rKJM0T8Q3B6J0QJcq==hA@mail.gmail.com>
 <8aac88e2a22cd84e50ee1a2bcf3da9b7@postgrespro.ru>
 <CAKFQuwY=eGGGe7E9xHkdR+8YnKXeA8xp-qfRMGFJrs-Hsb_D5Q@mail.gmail.com>
 <b8e12875ebec9e6d3107df5fa1129e1e@postgrespro.ru>
 <20200602193547.GA26240@momjian.us>
 <26906a54-d7cb-2f8e-eed7-e31660024694@postgrespro.ru>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <26906a54-d7cb-2f8e-eed7-e31660024694@postgrespro.ru>
User-Agent: Mutt/1.10.1 (2018-07-13)
Precedence: bulk

On Tue, Jun  2, 2020 at 11:42:01PM +0300, Pavel Luzanov wrote:
> Hello,
> 
> On 02.06.2020 22:35, Bruce Momjian wrote:
> > On Thu, May 28, 2020 at 12:21:14PM +0300, p.luzanov@postgrespro.ru wrote:
> > > WAL |-----------|-----+-----|-----+-----|-----+----->
> > > 
> > >                     a           b           c
> > > CP              +-----+     +-----+     +-----+
> > >                  b     e     b     e     b     e
> > > 
> > > Checkpointer process for point A starts at a(b) and ends at a(e).
> > > At the end of the work, CP makes a WAL record(plus symbol on WAL line).
> > > 
> > > Back to the max_wal_size description:
> > > "Maximum size to let the WAL grow to between automatic WAL checkpoints."
> > > 
> > > As I understand now, this is true when we talk about the checkpoint as a
> > > process.
> > > "Maximum size to let the WAL grow to between a(b) and b(e), between b(b) and c
> > > (e), etc".
> > What if we say:
> > 
> > 	"Maximum size to let the WAL grow during automatic WAL checkpoints."
> > 
> > That highlights the "process" part.
> > 
> Really, "during" is associated with the process, while "between" with
> points.
> 
> If there is no objection, simple patch attached.

Applied to all supported versions, thanks.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EnterpriseDB                             https://enterprisedb.com

  The usefulness of a cup is in its emptiness, Bruce Lee