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authorNeil Conway <neilc@samurai.com>2004-01-06 17:26:23 +0000
committerNeil Conway <neilc@samurai.com>2004-01-06 17:26:23 +0000
commitbc028beb166b704d3c3028961dd6905772bf3a2d (patch)
tree1820130965e4fa7e38bca860ec776bd0e1bab743 /doc/src
parentb0c4a50bbbbd62c444cb3806a97c1e51e2249cfd (diff)
downloadpostgresql-bc028beb166b704d3c3028961dd6905772bf3a2d.tar.gz
postgresql-bc028beb166b704d3c3028961dd6905772bf3a2d.zip
Make the 'wal_debug' GUC variable a boolean (rather than an integer), and
hide it behind #ifdef WAL_DEBUG blocks.
Diffstat (limited to 'doc/src')
-rw-r--r--doc/src/sgml/ref/show.sgml4
-rw-r--r--doc/src/sgml/runtime.sgml9
-rw-r--r--doc/src/sgml/wal.sgml21
3 files changed, 18 insertions, 16 deletions
diff --git a/doc/src/sgml/ref/show.sgml b/doc/src/sgml/ref/show.sgml
index 3087c92d9e6..85dbfdcedcc 100644
--- a/doc/src/sgml/ref/show.sgml
+++ b/doc/src/sgml/ref/show.sgml
@@ -1,5 +1,5 @@
<!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/show.sgml,v 1.34 2003/11/29 19:51:39 pgsql Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/show.sgml,v 1.35 2004/01/06 17:26:23 neilc Exp $
PostgreSQL documentation
-->
@@ -172,7 +172,7 @@ SHOW ALL;
.
.
.
- wal_debug | 0
+ wal_debug | off
wal_sync_method | fdatasync
(94 rows)
</programlisting>
diff --git a/doc/src/sgml/runtime.sgml b/doc/src/sgml/runtime.sgml
index 6caf5dd93ac..5ec155d24d9 100644
--- a/doc/src/sgml/runtime.sgml
+++ b/doc/src/sgml/runtime.sgml
@@ -1,5 +1,5 @@
<!--
-$PostgreSQL: pgsql/doc/src/sgml/runtime.sgml,v 1.228 2004/01/05 20:37:51 neilc Exp $
+$PostgreSQL: pgsql/doc/src/sgml/runtime.sgml,v 1.229 2004/01/06 17:26:22 neilc Exp $
-->
<Chapter Id="runtime">
@@ -2667,10 +2667,13 @@ dynamic_library_path = '/usr/local/lib/postgresql:/home/my_project/lib:$libdir'
</varlistentry>
<varlistentry>
- <term><varname>wal_debug</varname> (<type>integer</type>)</term>
+ <term><varname>wal_debug</varname> (<type>boolean</type>)</term>
<listitem>
<para>
- If nonzero, turn on WAL-related debugging output.
+ If true, emit WAL-related debugging output. This option is
+ only available if the <symbol>WAL_DEBUG</symbol> macro was
+ defined when <productname>PostgreSQL</productname> was
+ compiled.
</para>
</listitem>
</varlistentry>
diff --git a/doc/src/sgml/wal.sgml b/doc/src/sgml/wal.sgml
index 0883f202422..8d0127b9f94 100644
--- a/doc/src/sgml/wal.sgml
+++ b/doc/src/sgml/wal.sgml
@@ -1,4 +1,4 @@
-<!-- $PostgreSQL: pgsql/doc/src/sgml/wal.sgml,v 1.26 2003/11/29 19:51:38 pgsql Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/wal.sgml,v 1.27 2004/01/06 17:26:23 neilc Exp $ -->
<chapter id="wal">
<title>Write-Ahead Logging (<acronym>WAL</acronym>)</title>
@@ -19,10 +19,10 @@
transaction processing. Briefly, <acronym>WAL</acronym>'s central
concept is that changes to data files (where tables and indexes
reside) must be written only after those changes have been logged,
- that is, when log records have been flushed to permanent
- storage. If we follow this procedure, we do not need to flush
- data pages to disk on every transaction commit, because we know
- that in the event of a crash we will be able to recover the
+ that is, when log records describing the changes have been flushed
+ to permanent storage. If we follow this procedure, we do not need
+ to flush data pages to disk on every transaction commit, because we
+ know that in the event of a crash we will be able to recover the
database using the log: any changes that have not been applied to
the data pages will first be redone from the log records (this is
roll-forward recovery, also known as REDO) and then changes made by
@@ -187,7 +187,7 @@
<para>
There will be at least one 16 MB segment file, and will normally
not be more than 2 * <varname>checkpoint_segments</varname> + 1
- files. You can use this to estimate space requirements for WAL.
+ files. You can use this to estimate space requirements for <acronym>WAL</acronym>.
Ordinarily, when old log segment files are no longer needed, they
are recycled (renamed to become the next segments in the numbered
sequence). If, due to a short-term peak of log output rate, there
@@ -254,7 +254,7 @@
<para>
The <varname>wal_sync_method</varname> parameter determines how
<productname>PostgreSQL</productname> will ask the kernel to force
- WAL updates out to disk.
+ <acronym>WAL</acronym> updates out to disk.
All the options should be the same as far as reliability goes,
but it's quite platform-specific which one will be the fastest.
Note that this parameter is irrelevant if <varname>fsync</varname>
@@ -262,11 +262,10 @@
</para>
<para>
- Setting the <varname>wal_debug</varname> parameter to any nonzero
- value will result in each <function>LogInsert</function> and
+ Enabling the <varname>wal_debug</varname> configuration parameter
+ will result in each <function>LogInsert</function> and
<function>LogFlush</function> <acronym>WAL</acronym> call being
- logged to the server log. At present, it makes no difference what
- the nonzero value is. This option may be replaced by a more
+ logged to the server log. This option may be replaced by a more
general mechanism in the future.
</para>
</sect1>