User's Manual

130 Migration, release, recall, and deletion
Recovery priority (RecoveryPriority)
Maintenance priority (MaintenancePriority)
Default partition allocation and job priority policy
Default partition allocation and job priority policy is defined in the FSE configuration template for FSE
partition configuration. For details, see ”Template for FSE partitions - Recall and Allocation part” on
page 251.
Priority calculation
The resource allocation queue holds resource requests that are sorted and processed by their job priority.
The priorities of all jobs in the queue will be recalculated each time a job changes its status or resources
are released or newly added to the FSE implementation. These job priorities are dynamically increasing
according to their age and phase of the job. A new job enters the queue with its initial priority; in case this
priority is not high enough to be processed immediately, it is recalculated and increased over time thus
enabling each job to be processed in a reasonable time.
Depending on a job type, the priority formula differs for administration and backup jobs that have a
system-wide priority, and jobs that are associated with a particular FSE partition (migration, recall,
recovery, and maintenance). The priority calculation is based on the parameters set in the related partition
or system policy, and on several additional factors:
• Phase
The phase of a job increases if it requires additional resources. This is relevant for migration jobs when
the following is true:
• The phase is increased by 1 if a copy was made and other copies are still waiting for resources.
• The medium volume is full, therefore a new split for the file is needed.
It is also relevant for recall jobs when the following is true:
• The phase is increased by 1 when a split of a file is recalled which spans over multiple media
volumes.
Other jobs do not have a phase.
• TimeStep
The value by which the priority is increased for each elapsed second of ElapsedTime.
• JobTypePriority
Depending on the job type, the value of one of the following variables is used for this parameter:
• SystemAdminPriority, SystemBackupPriority (defined in the FSE system configuration
file)
• MigrationPriority, RecallPriority, RecoveryPriority, MaintPriority (defined in
the FSE partition configuration file)
• ElapsedTime
The time in seconds since the job was started.
• PhaseFactor
The value by which the priority of a job is increased after each phase.
Definition The priority for recovery jobs on a scale of 1 to 100.
Impact This priority is multiplied by the partition priority in order to calculate the initial priority of
a recovery job. See ”Priority calculation” on page 130.
Definition The priority for maintenance jobs on a scale of 1 to 100.
Impact This priority is multiplied by the partition priority in order to calculate the initial priority of
a maintenance job. See ”Priority calculation” on page 130.