ParallelJobs.rst

.. _parallel_jobs: Parallel Jobs ============= Avocado-VT ships with a plugin that creates a lock file in a known public location (``/tmp`` by default, but configurable) to prevent multiple runs of jobs that include VT tests. The reason is that, by default, multiple jobs running at the same can access the same data files and cause corruption. Example of data files are the guest images, which are usually modified, either directly or indirectly by the tests. Checking Installation --------------------- The vt-joblock is installed and registered by default. To make sure it's active, run:: $ avocado plugins The VT Job lock plugin should be listed:: Plugins that run before/after the execution of jobs (avocado.plugins.job.prepost): ... vt-joblock Avocado-VT Job Lock/Unlock ... Configuration ------------- The configuration for the vt-joblock plugin can be found at ``/etc/avocado/conf.d/vt_joblock.conf``. Example of a configuration file content follows:: [plugins.vtjoblock] # Directory where the lock file will be located. Avocado should have permission # to write to this directory. dir=/tmp The configuration key ``dir`` lets you set the directory where Avocado will look for an existing lock file before running, and create one if it doesn't exist yet. Running Parallel Jobs --------------------- Supposing that you have multiple users on a single machine, using different data directories, you can allow parallel VT jobs by setting different lock directories for each user. To do so, you can add the customized lock directory to the user's own Avocado configuration file. Start by creating a lock directory:: [user1@localhost] $ mkdir ~/avocado/data/avocado-vt/lockdir Then modify the user's own configuration to point to the newly created lock directory:: [user1@localhost] $ cat >> ~/.config/avocado/avocado.conf <