docs: Clarify --with-segsize-blocks documentation

Without the added "relation" it's not immediately clear that the option
relates to the relation segment size and not e.g. the WAL segment size.

The option was added in d3b111e32.

Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/837536.1695348498@sss.pgh.pa.us
Backpatch: 16-

diff --git a/doc/src/sgml/installation.sgml b/doc/src/sgml/installation.sgml
index ac8eee47c668fd1e32dd850ce1131bf0f65f4214..f4b1f811899fe68e133f68196cea62899e37e940 100644 (file)
--- a/doc/src/sgml/installation.sgml
+++ b/doc/src/sgml/installation.sgml
@@ -1681,7 +1681,7 @@ build-postgresql:
        <term><option>--with-segsize-blocks=SEGSIZE_BLOCKS</option></term>
        <listitem>
         <para>
-         Specify the segment size in blocks. If both
+         Specify the relation segment size in blocks. If both
          <option>--with-segsize</option> and this option are specified, this
          option wins.
 
@@ -3178,7 +3178,7 @@ ninja install
        <term><option>-Dsegsize_blocks=SEGSIZE_BLOCKS</option></term>
        <listitem>
         <para>
-         Specify the segment size in blocks. If both
+         Specify the relation segment size in blocks. If both
          <option>-Dsegsize</option> and this option are specified, this option
          wins.