LSF License Scheduler policies

LSF License Scheduler policies distribute license tokens among license projects, which you create and configure in the lsf.licensescheduler configuration file. The following cases describe how LSF License Scheduler policies can help license projects to share licenses.

Fair sharing

The License Scheduler distribution policy guarantees that each license project is entitled to a minimum portion of the available licenses.

Example

Create three LSF License Scheduler projects, and share the licenses equally. If one project does not need a license, another project can use it. In this case, dynamic redistribution of licenses maximizes utilization while enforcing the fair share policy.

Not all license projects in a cluster have a full workload at all times. Free licenses can be shared across projects, so that idle licenses for one project are available to other projects.

Round robin sharing

This example shows how to configure round robin sharing. Round robin sharing is required when there are fewer licenses than the number required by license projects. The policy can be configured in the same way as the fair sharing policy.

If the total number of licenses is smaller than the number required by license projects, and all projects need more licenses, then the projects take turns using the licenses.

Example

Create three LSF License Scheduler projects, and share the licenses equally. The projects take turns to use the license. The three license projects share one license.

Jobs having a run time of 5 to 10 minutes are pending for each of the three projects. The projects share the license based on round robin policy.

Preemption

This example shows how license ownership and preemption work.

License ownership gives license projects the right to use their licenses on demand, while still allowing LSF License Scheduler to distribute the licenses to other license projects when the owner is not using them.

Example

Create two LSF License Scheduler projects, Lp1 and Lp2, and share the licenses, but grant ownership of the licenses to one of the projects (Lp2).

When Lp2 has no work to be done, Lp1. can use the licenses. When Lp2 has work to do, Lp1 must return the license immediately to Lp2. The license utilization is always at the maximum, showing that all licenses are in use even while the license distribution policies are being enforced.