An RHQ user recently asked on our forums how to monitor "active connections" in a JBoss AS 7 web connector. Here is an how-to guide.
Let's assume that you already started a JBoss AS 7 instance, created a user in the Management Realm for RHQ agent (with
add-user script) and imported this instance in RHQ server.
Don't forget to configure the user credentials under the Connection Settings tab.
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| AS 7 Connection Settings |
By default, the JBoss Web subsystem uses an internal thread pool and does not expose many properties through the management interface. What we need to do is creating a dedicated thread pool in the Threads subsystem and configure it to be the web connector executor.
Create a thread factory
Wouldn't it be nice to give connector threads an eloquent name? A dedicated thread factory will help. Under the Inventory > Child Resources tab of the Threads subsystem page, create a new child of ThreadFactory type:
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| Create child of ThreadFactory type |
Give this thread factory a name and adjust the Thread Name Pattern as you wish:
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| ThreadFactory creation wizard |
WARNING: don't leave priority unset. The default value '-1' is not valid and things will break at thread creation time.
Create and configure a thread pool
This is the core part. Under the Inventory > Child Resources tab of the Threads subsystem page, create a new child of ThreadPool type. Choose the unbounded-queue-thread-pool template and don't forget to link with your thread factory:
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| ThreadPool creation wizard |
Once the thread pool has been created and the new resource discovered by RHQ, enable measurements (only availability check is enabled by default). I chose to keep the default value for total counts and check active threads count every 30 seconds:
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| ThreadPool Monitoring Schedules |
Configure the web connector
Almost done! Configure the web connector to use the new thread pool as executor:
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| Web Connector configuration |
This change requires to reload the JBoss AS 7 configuration. You can do this under the Operations tab of the JBoss AS 7 resource page.
Thread pool metrics
That's it! Now you can see your metrics collected:
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| Web Connector Executor metrics |
