Sun N1 Grid Engine 6.1 Administration Guide

Tickets

The share-based, functional, and override scheduling policies are implemented with tickets. Each policy has a pool of tickets. A policy allocates tickets to jobs as the jobs enter the multimachine grid engine system. Each routine policy that is in force allocates some tickets to each new job. The policy might also reallocate tickets to running jobs at each scheduling interval.

Tickets weight the three policies. For example, if no tickets are allocated to the functional policy, that policy is not used. If the functional ticket pool and the share-based ticket pool have an equal number of tickets, both policies have equal weight in determining a job's importance.

Tickets are allocated to the routine policies at system configuration by grid engine system managers. Managers and operators can change ticket allocations at any time with immediate effect. Additional tickets are injected into the system temporarily to indicate an override. Policies are combined by assignment of tickets. When tickets are allocated to multiple policies, a job gets a portion of each policy's tickets, which indicates the job's importance in each policy in force.

The grid engine system grants tickets to jobs that are entering the system to indicate their importance under each policy in force. At each scheduling interval, each running job can gain tickets, lose tickets, or keep the same number of tickets. For example, a job might gain tickets from an override. A job might lose tickets because it is getting more than its fair share of resources. The number of tickets that a job holds represent the resource share that the grid engine system tries to grant that job during each scheduling interval.

You configure a site's dynamic resource management strategy during installation. First, you allocate tickets to the share-based policy and to the functional policy. You then define the share tree and the functional shares. The share-based ticket allocation and the functional ticket allocation can change automatically at any time. The administrator manually assigns or removes tickets.