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[185.5.252.136]) by smtp.gmail.com with ESMTPSA id 38308e7fff4ca-39b1d81d0f8sm6152661fa.9.2026.06.30.08.04.55 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 30 Jun 2026 08:04:55 -0700 (PDT) Content-Type: multipart/alternative; boundary=Apple-Mail-8D79CEC2-1C74-4EC4-93D9-0F3D52A16201 Content-Transfer-Encoding: 7bit From: Yaroslav Saburov Mime-Version: 1.0 (1.0) Subject: Re: glossary Data page Date: Tue, 30 Jun 2026 18:04:53 +0300 Message-Id: References: Cc: pgsql-docs@lists.postgresql.org In-Reply-To: To: "David G. Johnston" X-Mailer: iPhone Mail (19H422) List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk --Apple-Mail-8D79CEC2-1C74-4EC4-93D9-0F3D52A16201 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Maybe these are just the intricacies of translation. This is how I interpret it: 1) All pages are the same size. 2) Data pages are usually stored on disk, 3) each in a separate file,=20 > 1) All pages are of the same size. > 2) Data pages are typically stored on disk > 3) each in a specific file, > 30 =D1=87=D0=B5=D1=80=D0=B2. 2026 =D1=80. =D0=BE 16:28 David G. Johnston <= david.g.johnston@gmail.com> =D0=BF=D0=B8=D1=88=D0=B5: >=20 > =EF=BB=BFOn Sunday, June 28, 2026, PG Doc comments form wrote: >> The following documentation comment has been logged on the website: >>=20 >> Page: https://www.postgresql.org/docs/18/glossary.html >> Description: >>=20 >> > The basic structure used to store relation data. All pages are of the s= ame >> size. Data pages are typically stored on disk, each in a specific file, a= nd >> can be read to shared buffers where they can be modified, becoming dirty.= >> They become clean when written to disk. New pages, which initially exist i= n >> memory only, are also dirty until written. >>=20 >> Am I correct in understanding from this description that all files on the= >> disk will be the same size? >> One page =3D one file? >=20 > No. A page is an atomic unit subset of a file. Files contain many pages.= It would be crazy to limit file sizes to 8kb when we have GB available. >=20 > David J.=20 --Apple-Mail-8D79CEC2-1C74-4EC4-93D9-0F3D52A16201 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable

Maybe these are just the intricacies of translation.=

This is how I interpret it:


1) All pages are the same size.

2) Data pages are usually stored on disk,<= /p>

3) each in a separate file, 


> 1) All pages are of the same size.

> 2) Data pages are typically stored on disk

> 3) each in a specific file,

=

30 =D1=87=D0=B5=D1=80=D0=B2. 2= 026 =D1=80. =D0=BE 16:28 David G. Johnston <david.g.johnston@gmail.c= om> =D0=BF=D0=B8=D1=88=D0=B5:

=EF=BB=BFOn Sunday, June 28, 2026, PG Doc comments f= orm <noreply@postgresql.org= > wrote:
The following documentation com= ment has been logged on the website:

Page: https://www.postgresql.org/docs/18/glossary.html
Description:

> The basic structure used to store relation data. All pages are of the s= ame
size. Data pages are typically stored on disk, each in a specific file, and<= br> can be read to shared buffers where they can be modified, becoming dirty. They become clean when written to disk. New pages, which initially exist in<= br> memory only, are also dirty until written.

Am I correct in understanding from this description that all files on the disk will be the same size?
One page =3D one file?

No.  A page is an atomic unit subset o= f a file.  Files contain many pages.  It would be crazy to limit f= ile sizes to 8kb when we have GB available.

David J= . 
= --Apple-Mail-8D79CEC2-1C74-4EC4-93D9-0F3D52A16201--