Launch Rockets through a queue

If your FireWorker is a large, shared resource (such as a computing cluster or supercomputing center), you probably won’t be able to launch Rockets directly. Instead, you’ll submit Rockets through an existing queueing system that allocates computer time.

Launch a single job through a queue

To get warmed up, let’s set things up so we can launch a single Rocket through a queueing system. The Queue Launcher helps launch Rockets through a queue.

Configure the Queue Launcher

The Queue Launcher needs to know how to communicate with your queue system and the executable to submit to the queue (in our case, a Rocket). These parameters are defined through a QueueParams file.

  1. Move to the queue tutorial directory on your FireWorker:

    cd <INSTALL_DIR>/fw_tutorials/queue
  2. Locate an appropriate QueueParams file. The files are usually named queueparams_<QUEUE>.yaml where <QUEUE> is the supported queue system.

Note

If you cannot find a working QueueParams file for your specific queuing system, please contact us for help! (see Contributing and Contact) We would like to support more queueing systems in FireWorks.

  1. Copy your chosen QueueParams file to a new name:

    cp queueparams_<QUEUE>.yaml my_qp.yaml
  2. Open my_qp.yaml and modify it as follows:

    1. In the part that specifies running rlauncher_run.py, modify the path/to/my_fworker.yaml to contain the absolute path of the my_fworker.yaml file on your machine. If you completed the previous tutorial, this is probably: <INSTALL_DIR>/fw_tutorials/installation_pt2/my_fworker.yaml
    2. On the same line, modify the path/to/my_launchpad.yaml to contain the absolute path of the my_launchpad.yaml file on your machine. This is probably: <INSTALL_DIR>/fw_tutorials/installation_pt2/my_launchpad.yaml
    3. For the logging_dir parameter, modify the path/to/logging text to contain the absolute path of where you would like FireWorks logs to go. For example, you might create a fw_logs directory inside your home directory, and point the logging_dir parameter there.

    Note

    Be sure to indicate the full, absolute path name; do not use BASH shortcuts like ‘.’, ‘..’, or ‘~’, and do not indicate a relative path. (also, do not pass Go!)

Add some FireWorks

Let’s reset our database and add a new FireWork, all from our FireWorker this time:

lp_run.py -l <PATH_TO_LAUNCHPAD> reset <TODAY'S DATE>
lp_run.py -l <PATH_TO_LAUNCHPAD> add fw_test.yaml

where <PATH_TO_LAUNCHPAD> is the location of your my_launchpad.yaml file.

Submit a job

  1. Try submitting a job using the command:

    qlauncher_run.py singleshot my_qp.yaml
  2. This should have submitted a job to the queue in the current directory. You can read the log files in the logging directory, and/or check the status of your queue to ensure your job appeared.

  3. After your queue manager runs your job, you should see the file howdy.txt in the current directory.

If everything ran successfully, congratulations! You just executed a complicated sequence of instructions:

  1. The Queue Launcher submitted a Rocket to your queue manager
  2. Your queue manager executed the Rocket when resources were ready
  3. The Rocket fetched a FireWork from the FireServer and ran the specification inside

Adding more power: using rapid-fire mode

While launching a single job to a queue is nice, a more powerful use case is to submit a large number of jobs at once, or to maintain a certain number of jobs in the queue. Like the Rocket Launcher, the Queue Launcher can be run in a “rapid-fire” mode that provides these features.

Add some FireWorks

Let’s reset our database and add three new FireWorks, all from our FireWorker:

lp_run.py -l <PATH_TO_LAUNCHPAD> reset <TODAY'S DATE>
lp_run.py -l <PATH_TO_LAUNCHPAD> add fw_test.yaml
lp_run.py -l <PATH_TO_LAUNCHPAD> add fw_test.yaml
lp_run.py -l <PATH_TO_LAUNCHPAD> add fw_test.yaml

where <PATH_TO_LAUNCHPAD> is the location of your my_launchpad.yaml file.

Unleash rapid-fire mode

  1. Navigate to a clean testing directory on the FireWorker:

    mkdir ~/rapidfire_tests
    cd ~/rapidfire_tests
  2. Copy your QueueParams file to this testing directory:

    cp <PATH_TO_MY_QUEUE_PARAMS> .

where <PATH_TO_MY_QUEUE_PARAMS> is the path to my_qp.yaml file that you created in the previous section.

  1. Looking inside my_qp.yaml, confirm that the path to my_fworker.yaml and my_launchpad.yaml are still valid. (They should be, unless you moved or deleted these files)

  2. Submit several jobs with a single command:

    qlauncher_run.py rapidfire -q 3 my_qp.yaml

    Important

    The Queue Launcher sleeps between each job submission to give time for the queue manager to ‘breathe’. It might take a few minutes to submit all the jobs.

    Important

    The command above submits jobs until you have at most 3 jobs in the queue. If you had some jobs existing in the queue before running this command, you might need to increase the -q parameter.

  3. The rapid-fire command should have created a directory beginning with the tag block_. Navigate inside this directory, and confirm that three directories starting with the tag launch were created. The launch directories contain your individual jobs.

You’ve now launched multiple Rockets with a single command!

Note

For more tips on the Queue Launcher, such as how to maintain a certain number of jobs in the queue indefinitely, read its built-in help: qlauncher_run.py rapidfire -h