-<!-- $PostgreSQL: pgsql/doc/src/sgml/backup.sgml,v 2.155 2010/05/03 09:14:16 heikki Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/backup.sgml,v 2.156 2010/06/07 02:01:08 itagaki Exp $ -->
<chapter id="backup">
<title>Backup and Restore</title>
<para>
It is also possible to use replication methods, such as
- <productname>Slony</>, to create a slave server with the updated version of
- <productname>PostgreSQL</>. The slave can be on the same computer or
+ <productname>Slony</>, to create a standby server with the updated version of
+ <productname>PostgreSQL</>. The standby can be on the same computer or
a different computer. Once it has synced up with the master server
(running the older version of <productname>PostgreSQL</>), you can
- switch masters and make the slave the master and shut down the older
+ switch masters and make the standby the master and shut down the older
database instance. Such a switch-over results in only several seconds
of downtime for an upgrade.
</para>
-<!-- $PostgreSQL: pgsql/doc/src/sgml/high-availability.sgml,v 1.70 2010/05/29 09:01:10 heikki Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/high-availability.sgml,v 1.71 2010/06/07 02:01:08 itagaki Exp $ -->
<chapter id="high-availability">
<title>High Availability, Load Balancing, and Replication</title>
</varlistentry>
<varlistentry>
- <term>Trigger-Based Master-Slave Replication</term>
+ <term>Trigger-Based Master-Standby Replication</term>
<listitem>
<para>
- A master-slave replication setup sends all data modification
+ A master-standby replication setup sends all data modification
queries to the master server. The master server asynchronously
- sends data changes to the slave server. The slave can answer
+ sends data changes to the standby server. The standby can answer
read-only queries while the master server is running. The
- slave server is ideal for data warehouse queries.
+ standby server is ideal for data warehouse queries.
</para>
<para>
<productname>Slony-I</> is an example of this type of replication, with per-table
- granularity, and support for multiple slaves. Because it
- updates the slave server asynchronously (in batches), there is
+ granularity, and support for multiple standby servers. Because it
+ updates the standby server asynchronously (in batches), there is
possible data loss during fail over.
</para>
</listitem>
this is unacceptable, either the middleware or the application
must query such values from a single server and then use those
values in write queries. Another option is to use this replication
- option with a traditional master-slave setup, i.e. data modification
+ option with a traditional master-standby setup, i.e. data modification
queries are sent only to the master and are propagated to the
- slaves via master-slave replication, not by the replication
+ standby servers via master-standby replication, not by the replication
middleware. Care must also be taken that all
transactions either commit or abort on all servers, perhaps
using two-phase commit (<xref linkend="sql-prepare-transaction">
replication is best for mostly read workloads, though its big
advantage is that any server can accept write requests —
there is no need to partition workloads between master and
- slave servers, and because the data changes are sent from one
+ standby servers, and because the data changes are sent from one
server to another, there is no problem with non-deterministic
functions like <function>random()</>.
</para>
<entry>Shared Disk Failover</entry>
<entry>File System Replication</entry>
<entry>Hot/Warm Standby Using PITR</entry>
- <entry>Trigger-Based Master-Slave Replication</entry>
+ <entry>Trigger-Based Master-Standby Replication</entry>
<entry>Statement-Based Replication Middleware</entry>
<entry>Asynchronous Multimaster Replication</entry>
<entry>Synchronous Multimaster Replication</entry>
</row>
<row>
- <entry>Slaves accept read-only queries</entry>
+ <entry>Standby accept read-only queries</entry>
<entry align="center"></entry>
<entry align="center"></entry>
<entry align="center">Hot only</entry>
partitioned by offices, e.g., London and Paris, with a server
in each office. If queries combining London and Paris data
are necessary, an application can query both servers, or
- master/slave replication can be used to keep a read-only copy
+ master/standby replication can be used to keep a read-only copy
of the other office's data on each server.
</para>
</listitem>
-<!-- $PostgreSQL: pgsql/doc/src/sgml/release-alpha.sgml,v 2.1 2010/04/29 20:54:28 momjian Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/release-alpha.sgml,v 2.2 2010/06/07 02:01:09 itagaki Exp $ -->
<sect1 id="release-9-0-alpha">
<title>Release 9.0alpha4</title>
<emphasis>This implementation should be significantly more
efficient than the old one, and is also more compatible with
Hot Standby usage. There is not yet any facility for HS
- slaves to receive notifications generated on the master,
+ standby servers to receive notifications generated on the master,
although such a thing is possible in future.</emphasis>
</para>
</listitem>
<listitem>
<para>
Allow read-only connections during recovery, also
- known as Hot Standby. This provides a built-in master-slave
+ known as Hot Standby. This provides a built-in master-standby
replication solution.
</para>
</listitem>