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doc: Improve references to term "FSM" in pageinspect and pgfreespacemap 

Author: Dong Wook Lee
Reviewed-by: Laurenz Albe
Discussion: https://postgr.es/m/CAAcBya+=F=HaHxJ7tGjAM1r=A=+bDbimpsex8Vqrb4GjqFDYsQ@mail.gmail.com
This commit is contained in:
Michael Paquier 2022-03-09 10:43:25 +09:00
parent 43e7787dd3
commit 7687ca996e
3 changed files with 21 additions and 17 deletions
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12
doc/src/sgml/pageinspect.sgml
View File

@ -31,9 +31,11 @@
relation and returns a copy as a <type>bytea</type> value. This allows a
single time-consistent copy of the block to be obtained.
<replaceable>fork</replaceable> should be <literal>'main'</literal> for
the main data fork, <literal>'fsm'</literal> for the free space map,
<literal>'vm'</literal> for the visibility map, or <literal>'init'</literal>
for the initialization fork.
the main data fork, <literal>'fsm'</literal> for the
<link linkend="storage-fsm">free space map</link>,
<literal>'vm'</literal> for the
<link linkend="storage-vm">visibility map</link>, or
<literal>'init'</literal> for the initialization fork.
</para>
</listitem>
</varlistentry>
@ -136,7 +138,7 @@ test=# SELECT page_checksum(get_raw_page('pg_class', 0), 0);
<listitem>
<para>
<function>fsm_page_contents</function> shows the internal node structure
of an FSM page. For example:
of an <acronym>FSM</acronym> page. For example:
<screen>
test=# SELECT fsm_page_contents(get_raw_page('pg_class', 'fsm', 0));
</screen>
@ -147,7 +149,7 @@ test=# SELECT fsm_page_contents(get_raw_page('pg_class', 'fsm', 0));
</para>
<para>
See <filename>src/backend/storage/freespace/README</filename> for more
information on the structure of an FSM page.
information on the structure of an <acronym>FSM</acronym> page.
</para>
</listitem>
</varlistentry>

17
doc/src/sgml/pgfreespacemap.sgml
View File

@ -9,10 +9,10 @@
<para>
The <filename>pg_freespacemap</filename> module provides a means for examining the
free space map (FSM). It provides a function called
<function>pg_freespace</function>, or two overloaded functions, to be
precise. The functions show the value recorded in the free space map for
a given page, or for all pages in the relation.
<link linkend="storage-fsm">free space map</link> (<acronym>FSM</acronym>).
It provides a function called <function>pg_freespace</function>, or two
overloaded functions, to be precise. The functions show the value recorded in
the free space map for a given page, or for all pages in the relation.
</para>
<para>
@ -36,7 +36,7 @@
<listitem>
<para>
Returns the amount of free space on the page of the relation, specified
by <literal>blkno</literal>, according to the FSM.
by <literal>blkno</literal>, according to the <acronym>FSM</acronym>.
</para>
</listitem>
</varlistentry>
@ -50,7 +50,8 @@
<listitem>
<para>
Displays the amount of free space on each page of the relation,
according to the FSM. A set of <literal>(blkno bigint, avail int2)</literal>
according to the <acronym>FSM</acronym>. A set of
<literal>(blkno bigint, avail int2)</literal>
tuples is returned, one tuple for each page in the relation.
</para>
</listitem>
@ -112,8 +113,8 @@ postgres=# SELECT * FROM pg_freespace('foo', 7);
<para>
Original version by Mark Kirkwood <email>markir@paradise.net.nz</email>.
Rewritten in version 8.4 to suit new FSM implementation by Heikki
Linnakangas <email>heikki@enterprisedb.com</email>
Rewritten in version 8.4 to suit new <acronym>FSM</acronym> implementation
by Heikki Linnakangas <email>heikki@enterprisedb.com</email>
</para>
</sect2>

9
doc/src/sgml/storage.sgml
View File

@ -603,10 +603,11 @@ tuple would otherwise be too big.
<para>
Each heap and index relation, except for hash indexes, has a Free Space Map
(FSM) to keep track of available space in the relation. It's stored
alongside the main relation data in a separate relation fork, named after the
filenode number of the relation, plus a <literal>_fsm</literal> suffix. For example,
if the filenode of a relation is 12345, the FSM is stored in a file called
(<acronym>FSM</acronym>) to keep track of available space in the relation.
It's stored alongside the main relation data in a separate relation fork,
named after the filenode number of the relation, plus a <literal>_fsm</literal>
suffix. For example, if the filenode of a relation is 12345, the
<acronym>FSM</acronym> is stored in a file called
<filename>12345_fsm</filename>, in the same directory as the main relation file.
</para>