5.4. Taverna Remote Execution

The Taverna Remote Execution plugin is a plugin for Taverna that allows workflows to be run on a Remote Execution Server.

To install the Remote Execution plugin use the Plugin Manager in the Tools Menu.

Remote execution from Taverna depends upon the presence of Remote Execution Servers already installed on the web. A default Remote Execution Server is available in the Taverna Utilities subsection under downloads on the Taverna sourceforge site.

5.4.1. Specifying Remote Execution Servers

After installation of the Remote Execution plugin, a new perspective "Execute Remotely" is available. Within the perspective, the user can select from the set of Remote Execution Servers on which workflows may be run. When specifying a new Remote Execution Server, the user should enter the details given by the owner of the server.

The Remote Execution Server on which a workflow is to be run can be chosen from the selection menu. If a valid connection is made to the server, for example MyServer, then a message "Loaded jobs from MyServer" will appear in the log window at the bottom of the perspective. If a valid connection cannot be made then the message "Could not load jobs from MyServer" will appear.

The chosen Remote Execution Server is periodically polled and the updated status messages will appear in the log window.

5.4.2. Running a workflow remotely

To run a workflow remotely, edit or load the workflow design as normal. Switch to the "Execute Remotely" perspective. if necessary, choose a Remote Execution Server from the menu. Press the "Run workflow remotely" button. If any inputs are required for the workflow run then they can be entered as normal.

Once a workflow has been sumitted to a Remote Execution Server, it is placed in a queue. The status of the queue is monitored every twenty seconds. When a submitted workflow reaches the front of the queue, when the Remote Execution Server has free resources, the workflow will enter a DEQUEUED state during which the server is initialized to run the workflow. Once the workflow has started running, its progress can be viewed by clicking on its entry in the list of jobs and clicking the View Progress button. Once the workflow has finished running, it will be marked as COMPLETE. The results can be viewed by clicking on the workflow's entry and then on the View Results button.