Running steps in parallel is a great way to reduce your build's running time, especially when you have a large test suite. Before doing this, however, you must first check which steps must run sequentially. All the other steps can now run in parallel to speed up pipeline execution. For more information, see Breaking Your Pipelines into Steps.
This can be tuned further by combining it with the priority tag, which can yield even better results. The priority tag, which can be set for any step, controls the priority of a step when there are parallel steps in a pipeline or multiple pipelines executing. For more information, see Bash Tags.