Author: jstephens
Date: 2006-03-05 01:08:20 +0100 (Sun, 05 Mar 2006)
New Revision: 1516
Log:
Update Cluster FAQ ("Can Cluster use swap?")
Modified:
trunk/refman-4.1/ndbcluster.xml
trunk/refman-5.0/ndbcluster.xml
trunk/refman-5.1/ndbcluster.xml
Modified: trunk/refman-4.1/ndbcluster.xml
===================================================================
--- trunk/refman-4.1/ndbcluster.xml 2006-03-04 17:25:54 UTC (rev 1515)
+++ trunk/refman-4.1/ndbcluster.xml 2006-03-05 00:08:20 UTC (rev 1516)
@@ -9810,13 +9810,33 @@
</para>
<para>
- Currently, Cluster is in-memory only. This means that all
- table data (including indexes) is stored in RAM. Therefore, if
- your data takes up 1GB of space and you want to replicate it
- once in the cluster, you need 2GB of memory to do so. This in
- addition to the memory required by the operating system and
- any applications running on the cluster computers.
+ In MySQL-¤t-series;, Cluster is in-memory only. This
+ means that all table data (including indexes) is stored in
+ RAM. Therefore, if your data takes up 1GB of space and you
+ want to replicate it once in the cluster, you need 2GB of
+ memory to do so. This in addition to the memory required by
+ the operating system and any applications running on the
+ cluster computers.
</para>
+
+ <para>
+ If a data node's memory usage exceeds what is available in
+ RAM, then the system will attempt to use swap space up to the
+ limit set for <literal>DataMemory</literal>. However, this
+ will at best result in severely degraded performance, and may
+ cuase the node to be dropped due to slow response time (missed
+ hearbeats). We do not recommend on relying on disk swapping in
+ a production environment for this reason. In any case, once
+ the <literal>DataMemory</literal> limit is reached, any
+ operations requiring additional memory (such as inserts) will
+ fail.
+ </para>
+
+ <para>
+ We are working to implement disk data storage for MySQL
+ Cluster in a future MySQL release series, but we have no plans
+ to add this capability in MySQL ¤t-series;.
+ </para>
<para>
You can use the following formula for obtaining a rough
Modified: trunk/refman-5.0/ndbcluster.xml
===================================================================
--- trunk/refman-5.0/ndbcluster.xml 2006-03-04 17:25:54 UTC (rev 1515)
+++ trunk/refman-5.0/ndbcluster.xml 2006-03-05 00:08:20 UTC (rev 1516)
@@ -10091,13 +10091,33 @@
</para>
<para>
- Currently, Cluster is in-memory only. This means that all
- table data (including indexes) is stored in RAM. Therefore, if
- your data takes up 1GB of space and you want to replicate it
- once in the cluster, you need 2GB of memory to do so. This in
- addition to the memory required by the operating system and
- any applications running on the cluster computers.
+ In MySQL-¤t-series;, Cluster is in-memory only. This
+ means that all table data (including indexes) is stored in
+ RAM. Therefore, if your data takes up 1GB of space and you
+ want to replicate it once in the cluster, you need 2GB of
+ memory to do so. This in addition to the memory required by
+ the operating system and any applications running on the
+ cluster computers.
</para>
+
+ <para>
+ If a data node's memory usage exceeds what is available in
+ RAM, then the system will attempt to use swap space up to the
+ limit set for <literal>DataMemory</literal>. However, this
+ will at best result in severely degraded performance, and may
+ cuase the node to be dropped due to slow response time (missed
+ hearbeats). We do not recommend on relying on disk swapping in
+ a production environment for this reason. In any case, once
+ the <literal>DataMemory</literal> limit is reached, any
+ operations requiring additional memory (such as inserts) will
+ fail.
+ </para>
+
+ <para>
+ We are working to implement disk data storage for MySQL
+ Cluster in a future MySQL release series, but we have no plans
+ to add this capability in MySQL ¤t-series;.
+ </para>
<para>
You can use the following formula for obtaining a rough
Modified: trunk/refman-5.1/ndbcluster.xml
===================================================================
--- trunk/refman-5.1/ndbcluster.xml 2006-03-04 17:25:54 UTC (rev 1515)
+++ trunk/refman-5.1/ndbcluster.xml 2006-03-05 00:08:20 UTC (rev 1516)
@@ -11723,6 +11723,11 @@
<emphasis>How much RAM do I need? Is it possible to use disk
memory at all?</emphasis>
</para>
+
+ <remark role="todo">
+ [js] Reword the following para when the Disk Data section is
+ ready.
+ </remark>
<para>
Currently, Cluster is in-memory only. This means that all
@@ -11732,6 +11737,32 @@
addition to the memory required by the operating system and
any applications running on the cluster computers.
</para>
+
+ <para>
+ If a data node's memory usage exceeds what is available in
+ RAM, then the system will attempt to use swap space up to the
+ limit set for <literal>DataMemory</literal>. However, this
+ will at best result in severely degraded performance, and may
+ cuase the node to be dropped due to slow response time (missed
+ hearbeats). We do not recommend on relying on disk swapping in
+ a production environment for this reason. In any case, once
+ the <literal>DataMemory</literal> limit is reached, any
+ operations requiring additional memory (such as inserts) will
+ fail.
+ </para>
+
+ <remark role="todo">
+ [js] Reword the following para and uncomment the xref when the
+ Disk Data section is ready.
+ </remark>
+
+ <para>
+ We are implementing disk data storage for clusters in MySQL
+ ¤t-series;, which will help to alleviate these issues,
+ and documentation showing how to use this capability will be
+ available in the near future.
+ <!-- See <xref linkend="mysql-cluster-disk-data"/>. -->
+ </para>
<para>
You can use the following formula for obtaining a rough
| Thread |
|---|
| • svn commit - mysqldoc@docsrva: r1516 - in trunk: refman-4.1 refman-5.0 refman-5.1 | jon | 5 Mar |
