pgsql: doc: Clarify CHECKPOINT handling of unlogged buffers

On Mon, 25 May 2026 at 11:23, Daniel Gustafsson
<dgustafsson@postgresql.org> wrote:

doc: Clarify CHECKPOINT handling of unlogged buffers

The CHECKPOINT reference page still described checkpoints as flushing
all data files, which could be misleading as it depends on the value
of FLUSH_UNLOGGED option. Update the description to make it clearer
that only data files of permanent relations are flushed by default.

Author: Chao Li <lic@highgo.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: /messages/by-id/4855807D-F1CA-44E6-9B58-406691832848@gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/377cc45194f4f1bd6eb68bd6eb42402e46e326d7

Modified Files
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doc/src/sgml/ref/checkpoint.sgml | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

"All data for permanent relations files will be flushed to disk, dirty
buffers of unlogged relations are not flushed unless
<literal>FLUSH_UNLOGGED</literal> is specified."

This doesn't quite read right.

"permanent relations files" should be "permanent relation files"

and the sentence looks like it should end after "flushed to disk",
with "Dirty buffers" being the start of a new sentence.

Regards

Thom