Application Execution

The next subsections describe how to execute applications with the COMPSs Python binding.

Environment

The following environment variables must be defined before executing a COMPSs Python application:

JAVA_HOME

Java JDK installation directory (e.g. /usr/lib/jvm/java-11-openjdk/)

Command

In order to run a Python application with COMPSs, the runcompss script can be used, like for Java and C/C++ applications. An example of an invocation of the script is:

compss@bsc:~$ runcompss \
                --lang=python \
                --pythonpath=$TEST_DIR \
                $TEST_DIR/application.py arg1 arg2

Or alternatively, use the pycompss module:

compss@bsc:~$ python -m pycompss \
                --pythonpath=$TEST_DIR \
                $TEST_DIR/application.py arg1 arg2

Tip

The runcompss command is able to detect the application language. Consequently, the --lang=python is not mandatory.

Tip

The --pythonpath flag enables the user to add directories to the PYTHONPATH environment variable and export them into the workers, so that the tasks can resolve successfully its imports.

Tip

PyCOMPSs applications can also be launched without parallelization (as a common python script) by avoiding the -m pycompss and its flags when using python:

compss@bsc:~$ python $TEST_DIR/application.py arg1 arg2

The main limitation is that the application must only contain @task, @binary and/or @mpi decorators and PyCOMPSs needs to be installed.

For full description about the options available for the runcompss command please check the Executing COMPSs applications Section.