Date: Mon, 8 Jul 2019 10:52:26 -0400
From: Stephen Frost <sfrost@snowman.net>
To: Thorsten =?iso-8859-1?Q?Sch=F6ning?= <tschoening@am-soft.de>
Cc: pgsql-admin@postgresql.org
Subject: Re: Does pg_start_backup changes how Postgres writes data?
Message-ID: <20190708145226.GZ29202@tamriel.snowman.net>
References: <171339952.20190708105025@am-soft.de>
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Greetings,

* Thorsten Sch=F6ning (tschoening@am-soft.de) wrote:
> From what I understand from reading the docs and multiple other
> sources, I have a different opinion: The only thing pg_start_backup
> changes regarding writes in the data directory of Postgres is that a
> checkpoint is done as part of starting the backup, even if no
> checkpoint would be needed currently otherwise. After that is done,

Magnus' already replied to most of this, but I wanted to point out that
you can control if pg_start_backup forces an immediate checkpoint or if
it waits for the checkpoint to complete naturally.

Thanks,

Stephen

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