Hadoop plugin questions; JMX

Elias Ross genman at noderunner.net
Thu Oct 20 01:15:10 UTC 2011


I'm seriously looking at the Hadoop plugin but have a couple of
comments and questions.

1. Not sure why the traditional JMX plugin was not used. Is the JMX
plugin not sufficient? I do notice the metrics across multiple MBeans
get grouped together nicely but I don't see much value in doing this.
Can I simply drop this code and start fresh? Or is this an approach
that should maybe be implemented in the JMX plugin itself. For
instance:

      <service name="Aggregate Service"
discovery="MBeanResourceDiscoveryComponent"
               description="Two MBeans in one service">

         <plugin-configuration>
            <c:simple-property name="objectName" readOnly="true"
default="captured"/> <!-- captured from the property name -->
         </plugin-configuration>
         <metric displayName="Foo"

property="hadoop:service=NameNode,name=FSNamesystemState|BlocksTotal"
                 description="Number of active threads in the system"/>

2. It's incomplete, obviously, and many of the metrics don't show up
with the Cloudera version I need, which is perhaps newer. I do intend
to fix this. Is there any need to keep what's there? (I'd say no.)

3. There are many values that are totals and available, so I'd like to
make ratios out of them. For example, if the total space is 1TB and
the available is 10GB, I'd like to set up an alert on < 10%
availability. What's the recommendation on how to alert on something
like this? (Maybe more of a user question, I guess.)

4. Are there tools for generating rhq-plugin.xml from an MBean server
connection? Basically it would spit out a <service> for each
ObjectName and properties and operations for each MBean attribute and
operation. I would think this could be fairly useful. The generated
plugin would obviously need to be edited by hand but this would save a
lot of work for many users.


More information about the rhq-devel mailing list