Hi Andres,
On 10/5/18 5:54 PM, Andres Freund wrote:
On 2018-09-20 11:48:08 -0400, David Steele wrote:
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index e1073ac6d3..3bfd172441 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -8440,10 +8440,8 @@ dynamic_library_path =
'C:\tools\postgresql;H:\my_project\lib;$libdir'
</term>
<listitem>
<para>
- Reports the number of blocks (pages) in a WAL segment file.
- The total size of a WAL segment file in bytes is equal to
- <varname>wal_segment_size</varname> multiplied by
<varname>wal_block_size</varname>;
- by default this is 16MB. See <xref linkend="wal-configuration"/> for
+ Reports the size of write ahead log segments.
+ The default value is 16MB. See <xref linkend="wal-configuration"/> for
more information.
</para>
</listitem>
Why is this actually more correct? You mean because we have a conversion
that does the mb conversion at display time?
In pre-11 versions of Postgres, you get this:
postgres=# select setting, unit from pg_settings where name =
'wal_segment_size';
setting | unit
---------+------
2048 | 8kB
But in v11 you get this:
select setting, unit from pg_settings where name = 'wal_segment_size';
setting | unit
----------+------
16777216 | B
So, while the WAL segment size used to be expressed in terms of 8K pages
it is now expressed in terms of absolute bytes. This seemed to me to be
a very deliberate change in the original commit so I guessed it was done
for clarity, but that the docs didn't get the message.
Regards,
--
-David
da...@pgmasters.net
