postgres.git / summary / log / commit / refs
commit 71c6a8e375b138af8aa46d80226ea9e98f2b94bc
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Date: Sat Jan 25 15:34:04 2014 +0000
First released in: 9.4.0
Add recovery_target='immediate' option.
This allows ending recovery as a consistent state has been reached. Without
this, there was no easy way to e.g restore an online backup, without
replaying any extra WAL after the backup ended.
MauMau and me.
doc/src/sgml/backup.sgml | 2 +-
doc/src/sgml/recovery-config.sgml | 44 ++++++++++++++++-------
src/backend/access/transam/recovery.conf.sample | 6 ++++
src/backend/access/transam/xlog.c | 46 ++++++++++++++++++++++++-
src/include/access/xlog.h | 3 +-
5 files changed, 86 insertions(+), 15 deletions(-)
diff --git a/doc/src/sgml/backup.sgml b/doc/src/sgml/backup.sgml
index a2361d780fb..854b5fde41c 100644
--- a/doc/src/sgml/backup.sgml
+++ b/doc/src/sgml/backup.sgml
@@ -1124,7 +1124,7 @@ restore_command = 'cp /mnt/server/archivedir/%f %p'
<para>
If you want to recover to some previous point in time (say, right before
the junior DBA dropped your main transaction table), just specify the
- required stopping point in <filename>recovery.conf</>. You can specify
+ required <link linkend="recovery-target-settings">stopping point</link> in <filename>recovery.conf</>. You can specify
the stop point, known as the <quote>recovery target</>, either by
date/time, named restore point or by completion of a specific transaction
ID. As of this writing only the date/time and named restore point options
diff --git a/doc/src/sgml/recovery-config.sgml b/doc/src/sgml/recovery-config.sgml
index 550cdce6f99..b818197299d 100644
--- a/doc/src/sgml/recovery-config.sgml
+++ b/doc/src/sgml/recovery-config.sgml
@@ -199,8 +199,33 @@ restore_command = 'copy "C:\\server\\archivedir\\%f" "%p"' # Windows
<sect1 id="recovery-target-settings">
<title>Recovery Target Settings</title>
+ <para>
+ By default, recovery will recover to the end of the WAL log. The
+ following parameters can be used to specify an earlier stopping point.
+ At most one of <varname>recovery_target</>,
+ <varname>recovery_target_name</>, <varname>recovery_target_time</>, or
+ <varname>recovery_target_xid</> can be specified.
+ </para>
<variablelist>
+ <varlistentry id="recovery-target" xreflabel="recovery_target_name">
+ <term><varname>recovery_target</varname><literal> = 'immediate'</literal></term>
+ <indexterm>
+ <primary><varname>recovery_target</> recovery parameter</primary>
+ </indexterm>
+ <listitem>
+ <para>
+ This parameter specifies that recovery should end as soon as a
+ consistency is reached, ie. as early as possible. When restoring from an
+ online backup, this means the point where taking the backup ended.
+ </para>
+ <para>
+ Technically, this is a string parameter, but <literal>'immediate'</>
+ is currently the only allowed value.
+ </para>
+ </listitem>
+ </varlistentry>
+
<varlistentry id="recovery-target-name" xreflabel="recovery_target_name">
<term><varname>recovery_target_name</varname>
(<type>string</type>)
@@ -212,10 +237,6 @@ restore_command = 'copy "C:\\server\\archivedir\\%f" "%p"' # Windows
<para>
This parameter specifies the named restore point, created with
<function>pg_create_restore_point()</> to which recovery will proceed.
- At most one of <varname>recovery_target_name</>,
- <xref linkend="recovery-target-time"> or
- <xref linkend="recovery-target-xid"> can be specified. The default is to
- recover to the end of the WAL log.
</para>
</listitem>
</varlistentry>
@@ -231,10 +252,6 @@ restore_command = 'copy "C:\\server\\archivedir\\%f" "%p"' # Windows
<para>
This parameter specifies the time stamp up to which recovery
will proceed.
- At most one of <varname>recovery_target_time</>,
- <xref linkend="recovery-target-name"> or
- <xref linkend="recovery-target-xid"> can be specified.
- The default is to recover to the end of the WAL log.
The precise stopping point is also influenced by
<xref linkend="recovery-target-inclusive">.
</para>
@@ -254,15 +271,18 @@ restore_command = 'copy "C:\\server\\archivedir\\%f" "%p"' # Windows
start, transactions can complete in a different numeric order.
The transactions that will be recovered are those that committed
before (and optionally including) the specified one.
- At most one of <varname>recovery_target_xid</>,
- <xref linkend="recovery-target-name"> or
- <xref linkend="recovery-target-time"> can be specified.
- The default is to recover to the end of the WAL log.
The precise stopping point is also influenced by
<xref linkend="recovery-target-inclusive">.
</para>
</listitem>
</varlistentry>
+ </variablelist>
+ <para>
+ The following options further specify the recovery target, and affect
+ what happens when the target is reached:
+ </para>
+
+ <variablelist>
<varlistentry id="recovery-target-inclusive"
xreflabel="recovery_target_inclusive">
diff --git a/src/backend/access/transam/recovery.conf.sample b/src/backend/access/transam/recovery.conf.sample
index 673605cfc66..6f7b38eb197 100644
--- a/src/backend/access/transam/recovery.conf.sample
+++ b/src/backend/access/transam/recovery.conf.sample
@@ -81,6 +81,12 @@
#recovery_target_inclusive = true
#
#
+# Alternatively, you can request stopping as soon as a consistent state
+# is reached, by uncommenting this option.
+#
+#recovery_target = 'immediate'
+#
+#
# If you want to recover into a timeline other than the "main line" shown in
# pg_control, specify the timeline number here, or write 'latest' to get
# the latest branch for which there's a history file.
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 9559d6d6aef..b333d820c72 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -5434,6 +5434,19 @@ readRecoveryCommandFile(void)
(errmsg_internal("recovery_target_name = '%s'",
recoveryTargetName)));
}
+ else if (strcmp(item->name, "recovery_target") == 0)
+ {
+ if (strcmp(item->value, "immediate") == 0)
+ recoveryTarget = RECOVERY_TARGET_IMMEDIATE;
+ else
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("invalid recovery_target parameter"),
+ errhint("The only allowed value is 'immediate'")));
+ ereport(DEBUG2,
+ (errmsg_internal("recovery_target = '%s'",
+ item->value)));
+ }
else if (strcmp(item->name, "recovery_target_inclusive") == 0)
{
/*
@@ -5676,7 +5689,20 @@ recoveryStopsBefore(XLogRecord *record)
bool isCommit;
TimestampTz recordXtime = 0;
- /* We only consider stopping before COMMIT or ABORT records. */
+ /* Check if we should stop as soon as reaching consistency */
+ if (recoveryTarget == RECOVERY_TARGET_IMMEDIATE && reachedConsistency)
+ {
+ ereport(LOG,
+ (errmsg("recovery stopping after reaching consistency")));
+
+ recoveryStopAfter = false;
+ recoveryStopXid = InvalidTransactionId;
+ recoveryStopTime = 0;
+ recoveryStopName[0] = '\0';
+ return true;
+ }
+
+ /* Otherwise we only consider stopping before COMMIT or ABORT records. */
if (record->xl_rmid != RM_XACT_ID)
return false;
record_info = record->xl_info & ~XLR_INFO_MASK;
@@ -5825,6 +5851,19 @@ recoveryStopsAfter(XLogRecord *record)
}
}
+ /* Check if we should stop as soon as reaching consistency */
+ if (recoveryTarget == RECOVERY_TARGET_IMMEDIATE && reachedConsistency)
+ {
+ ereport(LOG,
+ (errmsg("recovery stopping after reaching consistency")));
+
+ recoveryStopAfter = true;
+ recoveryStopXid = InvalidTransactionId;
+ recoveryStopTime = 0;
+ recoveryStopName[0] = '\0';
+ return true;
+ }
+
return false;
}
@@ -6246,6 +6285,9 @@ StartupXLOG(void)
ereport(LOG,
(errmsg("starting point-in-time recovery to \"%s\"",
recoveryTargetName)));
+ else if (recoveryTarget == RECOVERY_TARGET_IMMEDIATE)
+ ereport(LOG,
+ (errmsg("starting point-in-time recovery to earliest consistent point")));
else
ereport(LOG,
(errmsg("starting archive recovery")));
@@ -7125,6 +7167,8 @@ StartupXLOG(void)
snprintf(reason, sizeof(reason),
"at restore point \"%s\"",
recoveryStopName);
+ else if (recoveryTarget == RECOVERY_TARGET_IMMEDIATE)
+ snprintf(reason, sizeof(reason), "reached consistency");
else
snprintf(reason, sizeof(reason), "no recovery target specified");
diff --git a/src/include/access/xlog.h b/src/include/access/xlog.h
index 281f51629e4..47e302276b4 100644
--- a/src/include/access/xlog.h
+++ b/src/include/access/xlog.h
@@ -173,7 +173,8 @@ typedef enum
RECOVERY_TARGET_UNSET,
RECOVERY_TARGET_XID,
RECOVERY_TARGET_TIME,
- RECOVERY_TARGET_NAME
+ RECOVERY_TARGET_NAME,
+ RECOVERY_TARGET_IMMEDIATE
} RecoveryTargetType;
extern XLogRecPtr XactLastRecEnd;
[parent: 820f08cabdcb]