Running Synchronously

The simplest way to start PDriver is to run it synchronously. This runs through each block of the PDS script, waiting for each step to complete. This is the easiest way to run a test script, provided you don’t mind waiting for the results.

For example, here is a very simple PDS script, let us call it simplejob.pds:

job simplejob
    
task 10
    log "hello, world"
end
end job

This PDS script contains a single job block, and nothing more. It creates ten tasks and each one writes a hello message to the Engine log.

Run this script by typing the following code:

pdriver simplejob.pds

This launches PDriver, sends the ten tasks to the grid, and waits for the results to return. The Driver log messages are printed on your console window, and you can see as each task is submitted to and received from the Engines running on your grid. The Driver logs are also captured in a timestamped file created in a log directory; this directory is created in the directory PDriver is invoked in.

This quick example doesn’t do much, except for writing to a log. But a more complex script gives each Engine an executable to run, with different inputs for each task. More advanced scripting can possibly move data files or initialize databases before jobs or tasks are run, and results can be collected after each job or task.

For now, you can see the results of simplejob in the Engine log files. To do this:

1.

In the Administration Tool, go to Grid Components > Engines > Engine Admin.

2.

Select an Engine from the list.

3.

Click the Actions link, and select Log Files. This opens a window containing a list of links to the Engine logs on that Engine.

4.

Click a link to view the most recent log, and you’ll see the “hello, world” message written by each task of the simple job.