Platform LSF Administration Guide Version 6.2

Chapter 15
Specifying Resource Requirements
Administering Platform LSF
263
About Resource Requirement Strings
Most LSF commands accept a -R res_req argument to specify resource
requirements. The exact behaviour depends on the command. For example, specifying
a resource requirement for the
lsload command displays the load levels for all hosts
that have the requested resources.
Specifying resource requirements for the
lsrun command causes LSF to select the best
host out of the set of hosts that have the requested resources.
A resource requirement string describes the resources a job needs. LSF uses resource
requirements to select hosts for remote execution and job execution.
Resource requirement string sections
A selection section (select). The selection section specifies the criteria for
selecting hosts from the system.
An ordering section (order). The ordering section indicates how the hosts that
meet the selection criteria should be sorted.
A resource usage section (rusage). The resource usage section specifies the
expected resource consumption of the task.
A job spanning section (span). The job spanning section indicates if a parallel batch
job should span across multiple hosts.
A same resource section (same). The same section indicates that all processes of a
parallel job must run on the same type of host.
Which sections
apply
Depending on the command, one or more of these sections may apply. For example:
bsub uses all sections
lshosts only selects hosts, but does not order them
lsload selects and orders hosts
lsplace uses the information in select, order, and rusage sections to select
an appropriate host for a task
lsloadadj uses the rusage section to determine how the load information
should be adjusted on a host
Syntax
select[selection_string] order[order_string]
rusage[usage_string
[
, usage_string
][||
usage_string
]
...
] span[span_string] same[same_string]
The square brackets must be typed as shown.
The section names are s
elect, order, rusage, span, and same. Sections that do not
apply for a command are ignored.
If no section name is given, then the entire string is treated as a selection string. The
select keyword may be omitted if the selection string is the first string in the resource
requirement.
Each section has a different syntax.
How queue-level and job-level requirements are resolved
If job-level resource requirements are specified together with queue-level resource
requirements: