...
The workflow engine works by having "JobDaemons" for each type of batch system (LSF, Condor, SLURM etc). In the case of pilot jobs we use a special daemon called the PilotJobDaemon, which does not submit jobs to a batch system, but instead keeps the jobs in an internal queue until a pilot job comes and pulls them out of the queue to execute them. For the most part, using a PilotJobDaemon instead of a traditional job daemon is transparent to the workflow engine, and the developer of specific workflows.
...