Author: dmeil
Date: Wed Sep 14 19:55:57 2011
New Revision: 1170819
URL: http://svn.apache.org/viewvc?rev=1170819&view=rev
Log:
HBASE-4408. book.xml, faq
Modified:
hbase/trunk/src/docbkx/book.xml
Modified: hbase/trunk/src/docbkx/book.xml
URL:
http://svn.apache.org/viewvc/hbase/trunk/src/docbkx/book.xml?rev=1170819&r1=1170818&r2=1170819&view=diff
==============================================================================
--- hbase/trunk/src/docbkx/book.xml (original)
+++ hbase/trunk/src/docbkx/book.xml Wed Sep 14 19:55:57 2011
@@ -1703,6 +1703,23 @@ hbase> describe 't1'</programlisting>
<qandaset defaultlabel='faq'>
<qandadiv><title>General</title>
<qandaentry>
+ <question><para>When should I use HBase?</para></question>
+ <answer>
+ <para>
+ Anybody can download and give HBase a spin, even on a laptop.
The scope of this answer is when
+ would it be best to use HBase in a <emphasis>real</emphasis>
deployment.
+ </para>
+ <para>First, make sure you have enough hardware. Even HDFS
doesn't do well with anything less than
+ 5 DataNodes (due to things such as HDFS block replication
which has a default of 3), plus a NameNode.
+ Second, make sure you have enough data. HBase isn't suitable
for every problem. If you have
+ hundreds of millions or billions of rows, then HBase is a good
candidate. If you only have a few
+ thousand/million rows, then using a traditional RDBMS might be
a better choice due to the
+ fact that all of your data might wind up on a single node (or
two) and the rest of the cluster may
+ be sitting idle.
+ </para>
+ </answer>
+ </qandaentry>
+ <qandaentry>
<question><para>Are there other HBase FAQs?</para></question>
<answer>
<para>
@@ -1738,18 +1755,6 @@ hbase> describe 't1'</programlisting>
</para>
</answer>
</qandaentry>
- <qandaentry xml:id="brand.new.compressor">
- <question><para>Why are logs flooded with '2011-01-10 12:40:48,407
INFO org.apache.hadoop.io.compress.CodecPool: Got
- brand-new compressor' messages?</para></question>
- <answer>
- <para>
- Because we are not using the native versions of compression
- libraries. See <link
xlink:href="https://issues.apache.org/jira/browse/HBASE-1900";>HBASE-1900 Put
back native support when hadoop 0.21 is released</link>.
- Copy the native libs from hadoop under hbase lib dir or
- symlink them into place and the message should go away.
- </para>
- </answer>
- </qandaentry>
</qandadiv>
<qandadiv xml:id="ec2"><title>EC2</title>
<qandaentry>
@@ -1796,6 +1801,18 @@ When I build, why do I always get <code>
</para>
</answer>
</qandaentry>
+ <qandaentry xml:id="brand.new.compressor">
+ <question><para>Why are logs flooded with '2011-01-10 12:40:48,407
INFO org.apache.hadoop.io.compress.CodecPool: Got
+ brand-new compressor' messages?</para></question>
+ <answer>
+ <para>
+ Because we are not using the native versions of compression
+ libraries. See <link
xlink:href="https://issues.apache.org/jira/browse/HBASE-1900";>HBASE-1900 Put
back native support when hadoop 0.21 is released</link>.
+ Copy the native libs from hadoop under hbase lib dir or
+ symlink them into place and the message should go away.
+ </para>
+ </answer>
+ </qandaentry>
</qandadiv>
<qandadiv><title>How do I...?</title>
<qandaentry xml:id="secondary.indices">
