Re: clarify "rewritten" in pg_checksums docs

Hi,

Am Dienstag, den 01.09.2020, 15:29 +0200 schrieb Daniel Gustafsson:
> > On 1 Sep 2020, at 15:13, Michael Banck <michael.banck@credativ.de> wrote:
> > the pg_checksums docs mention that "When enabling checksums, every file
> > in the cluster is rewritten".
> > 
> > From IRC discussions, "rewritten" seems ambiguous, it could mean that a
> > second copy of the file is written and then switched over, implying
> > increased storage demand during the operation.
> 
> Makes sense, I can see that confusion.
> 
> > So maybe "rewritten in-place" is better, as per the attached?
> 
> Isn't "modified in-place" a more accurate description of the process?

AIUI we do rewrite the whole file (block by block, after updating the
page header with the checksum), so yeah, I though about using modified
instead but then decided rewritten is pretty (or even more) accurate.


Michael

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