-<!-- $PostgreSQL: pgsql/doc/src/sgml/high-availability.sgml,v 1.9 2006/11/22 03:44:52 momjian Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/high-availability.sgml,v 1.10 2006/11/22 04:00:19 momjian Exp $ -->
<chapter id="high-availability">
<title>High Availability and Load Balancing</title>
</varlistentry>
<varlistentry>
- <term>Multi-Master Clustering</term>
+ <term>Multi-Master Replication</term>
<listitem>
<para>
- In clustering, each server can accept write requests, and
- modified data is transmitted from the original server to every
- other server before each transaction commits. Heavy write
- activity can cause excessive locking, leading to poor performance.
- In fact, write performance is often worse than that of a single
- server. Read requests can be sent to any server. Some
- implementations use cluster-wide shared memory or shared disk
- to reduce the communication overhead. Clustering 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 server to another,
+ In multi-master replication, each server can accept write
+ requests, and modified data is transmitted from the original
+ server to every other server before each transaction commits.
+ Heavy write activity can cause excessive locking, leading to
+ poor performance. In fact, write performance is often worse
+ than that of a single server. Read requests can be sent to
+ any server. Some implementations use cluster-wide shared memory
+ or shared disk to reduce the communication overhead. Clustering
+ 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 server to another,
there is no problem with non-deterministic functions like
<function>random()</>.
</para>
</varlistentry>
<varlistentry>
- <term>Clustering For Parallel Query Execution</term>
+ <term>Multi-Server Parallel Query Execution</term>
<listitem>
<para>