Using JavaTM VisualVM¶
Java VisualVM is a JMX client included with the Java Development Kit (JDK) version 6 or higher. This section explains how to use VisualVM to monitor Virtual DataPort.
To run VisualVM, execute:
VisualVM is not included with the Denodo Platform. To obtain it, download the Java Development Kit (JDK). The Java Runtime Environment (JRE) does not include it either.
After launching it, install the “VisualVM-MBeans” plugin. To do this, click Plugins on the Tools menu. Click the Available plugins tab, select the “VisualVM-MBeans” check box and then, Install. In the wizard, click Next to proceed with the installation of the plugin.
After installing the plugin, connect to the JMX interface of Virtual
DataPort. To do this, click Add JMX Connection on the File menu.
In this dialog, in the Connection text field, enter
Then, select Use security credentials, enter the credentials of an administrator user and click Ok. After this, there will be a new element in the list of processes on the left-side of JVisualVM. Double-click it to open it. You can check that you have opened the right process by making sure that in the “Overview” tab, the “Arguments” label starts with “com.denodo.vdb.vdbinterface.server.VDBManagerImpl”
By clicking the different tabs of the process, you can obtain several information about the Virtual DataPort server: CPU consumption, memory consumption, activity of the Java garbage collector, etc. In this section, we will talk about the specific information provided by Virtual DataPort through its MBeans.
Click the MBeans tab to see the MBeans published by Virtual DataPort. Virtual DataPort server.
The information and events provided by each MBean is described in the following sections.
The information and events regarding DML statements (
DELETE, etc.) are accessible via the MBeans
of the category
section Information and Events on the Running of Statements). Unfold
this folder to see the list of the existing databases and unfold each
database to get information about the DML statements run on this
database. For example, Attributes tab of the RequestsManagementInfo
MBean shows the information on the queries run on the support
database, total number of requests executed (
and number of active requests at that time (
To view more details about a request, double-click its “Value” cell. The
data about each statement includes the type of statement executed
INSERT, etc.), the user who has run it, the time at
which it was run, the VQL statement, etc.
The events related to DML statements from the support database can be seen by clicking on the Notifications tab and then the Subscribe button. From then on, every time the Server executes a DML statement, VisualVM will display a new notification in this tab. Double-click the UserData cell for details on the statement run (see Details of a notification).