Chapter 4: ServiceMap Document: Advanced Features

• Including pre-defined methods: The services created by the toolkit have four pre-defined methods/operations viz. Shutdown, Kill and Ping. Shutdown will un-register the service's WSDL from the Registry service, wait for all application instances started by the application service to finish and then shutdown the service. After the shutdown operation is called, the service will not accept any connections. The Kill method will un-register the service's WSDL from the Registry service, kill all application instances started by the service and shutdown the service. The Ping operation can be used to 'ping' the service to see if it is running and responding. To enable these three methods in your service, include the following XML in your ServiceMap document

<method userDefined="false">
    <methodName>Ping</methodName>
    <methodDescription>Just ping the service</methodDescription>
</method>

<method userDefined="false">
    <methodName>Shutdown</methodName>
    <methodDescription>Shutdown the service</methodDescription>
</method>

<method userDefined="false">
    <methodName>Kill</methodName>
    <ethodDescription>Kill the service</methodDescription>
</method>

Note: The 'Shutdown' and Kill methods can be invoked directly or indirectly by sending either a SIG_TERM (TERM signal), SIG_HUP (caused by a log out) or by a SIG_INT (cause by control-c) to the service.

• Specifying job attributes: The application service provider can specify some attributes for running the application on a cluster of machines. These attributes must be specified within the "application" element in the ServiceMap document as shown below. These values can be modified by the user before invoking the application service.

<application>
    <applicationName targetNamespace="http://www.extreme.indiana.edu/lead">TestApp</applicationName>
    <project>
        <projectName>TG-ASC060000N</projectName>
        <projectDescription>LEAD Account on TeraGrid</projectDescription>
    </project>
    <queue>
        <queueName>test_queue</queueName>
        <queueDescription>Test queue</queueDescription>
    </queue>
    <count>
        <value>10</value>
        <decription>Run 10 counts of the application<description>
    </count>
    <!-- The application is an MPI applications -->
    <jobType>mpi</jobType>
</application>

The "projectName" is the account string used to execute the application. The "queueName" is the queue to submit the job if there is a batch scheduler on the cluster. The "count" is the number counts of the application to run. If the application is an MPI (Message Passing Interface) application, the "jobType" must be specified as "mpi".

• Specifying a lifetime for the service: The services created by the toolkit support lifetime management. They renew their WSDLs with a well known Registry Service at regular intervals of time.  You can specify the lifetime for a service in terms of the number of minutes of inactivity. After the specified period of inactivity, the service will un-register its WSDL from the Registry and shutdown. The period of inactivity is measured from the time the service sends the last response message to a client (not the time it receives the last request message from a client). You can specify the lifetime as shown below. The service will shutdown after 60 minutes after sending the last response message to the client.
  

[ << ] [ < ] [ Home ] [ > ] [ >> ]