Helix is intended mainly as an interactive system, where users log in and run commands or programs directly on the command line. If users wish to run commands at a later time, the Unix/Linux at command facilitates this. at will allow you to specify when a command should be run. Type 'man at' while logged on to helix, for more information.
Portable Batch System (PBS) [Biowulf]
Jobs on the Biowulf cluster are managed by the PBS Pro batch system, which allows users to submit jobs without regard for what resources (cpu, memory, networks) are available. When those resources become available the batch system will start the job. For more information, see the Biowulf user guide.
swarm is a program designed to simplify submitting a group of commands to the cluster. Some programs do not scale well and thus are not suited to true parallelizing. Other programs may be such that each individual job is very short, but many such jobs need to be run. Such programs are well suited to running 'swarms of single-threaded jobs'. swarm simplifies this process.