Class PolicyManager

Constructor

Expects fully-constructed policies (these are currently loaded in the Manager class, based on the config file).

Arguments: admission -- A child of LeaseAdmissionPolicy preemption -- A child of PreemptabilityPolicy host_selection -- A child of HostSelectionPolicy

Overrides: object.__init__

Sorts a list of leases by their preemptability

Takes a list of leases (the "preemptees"), determines their preemptability by another lease (the "preemptor"), and returns a list with the leases sorted by decreasing preemptability score (most preemptable leases first)

See documentation of PreemptabilityPolicy.get_lease_preemptability_score for more details on the preemptability score.

Argument preemptor -- Preemptor lease preemptees -- List of preemptee leases time -- Time at which preemption would take place

Sorts a list of hosts by their score

Takes a list of hosts, determines their score, and sorts them in order of decreasing score (most desireable hosts first)

See documentation of HostSelectionPolicy.get_host_score for more details.

Arguments: nodes -- List of physical node (the integer identifier used in the slot table) time -- Time at which the lease might be scheduled lease -- Lease that is being scheduled.

Lease admission function

Returns True if the lease can be accepted, False if it should be rejected.

Argument lease -- Lease request

Computes the lease preemptability score

See documentation of PreemptabilityPolicy.get_lease_preemptability_score for more details.

Arguments: preemptor -- Preemptor lease preemptee -- Preemptee lease time -- Time at which preemption would take place

Computes the score of a host

See documentation of HostSelectionPolicy.get_host_score for more details.

Arguments: node -- Physical node (the integer identifier used in the slot table) time -- Time at which the lease might be scheduled lease -- Lease that is being scheduled.