Platform LSF Administration Guide Version 6.2
Job Submission
Administering Platform LSF
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Job Submission
The life cycle of a job starts when you submit the job to LSF. On the command line,
bsub is used to submit jobs, and you can specify many options to bsub to modify the
default behavior. Jobs must be submitted to a queue.
Queues
Queues represent a set of pending jobs, lined up in a defined order and waiting for their
opportunity to use resources. Queues implement different job scheduling and control
policies. All jobs submitted to the same queue share the same scheduling and control
policy. Queues do not correspond to individual hosts; each queue can use all server hosts
in the cluster, or a configured subset of the server hosts.
A queue is a network-wide holding place for jobs. Jobs enter the queue via the
bsub
command. LSF can be configured to have one or more default queues. Jobs that are not
submitted to a specific queue will be assigned to the first default queue that accepts
them. Queues have the following attributes associated with them:
◆
Priority, where a larger integer is a higher priority
◆
Name, which uniquely identifies the queue
◆
Queue limits, that restrict hosts, number of jobs, users, groups, processors, etc.
◆
Standard UNIX limits: memory, swap, process, CPU, etc.
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Scheduling policies: FCFS, fairshare, preemptive, exclusive
◆
Administrators
◆
Run conditions
◆
Load-sharing threshold conditions, which apply load sharing to the queue
◆
UNIX nice(1) value, which sets the UNIX scheduler priority
Example queue
Begin Queue
QUEUE_NAME = normal
PRIORITY = 30
STACKLIMIT= 2048
DESCRIPTION = For normal low priority jobs, running only if
hosts are lightly loaded.
QJOB_LIMIT = 60 # job limit of the queue
PJOB_LIMIT = 2 # job limit per processor
ut = 0.2
io = 50/240
USERS = all
HOSTS = all
NICE = 20
End Queue
Queue priority
Defines the order in which queues are searched to determine which job will be
processed. Queues are assigned a priority by the LSF administrator, where a higher
number has a higher priority. Queues are serviced by LSF in order of priority from the
highest to the lowest. If multiple queues have the same priority, LSF schedules all the
jobs from these queues in first-come, first-served order.