Administering Platform LSF - SAS

About Resource Allocation Limits
About Resource Allocation Limits
Contents ◆ “What resource allocation limits do” on page 258
◆ “How LSF enforces limits” on page 259
◆ “How LSF counts resources” on page 259
◆ “Limits for resource consumers” on page 260
What resource allocation limits do
Jobs must specify
resource
requirements
By default, resource consumers like users, hosts, queues, or projects are not
limited in the resources available to them for running jobs. Resource
allocation limits configured in lsb.resources restrict:
◆ The maximum amount of a resource requested by a job that can be
allocated during job scheduling for different classes of jobs to start
◆ Which resource consumers the limits apply to
If all of the resource has been consumed, no more jobs can be started until
some of the resource is released.
For example, by limiting maximum amount of memory for each of your hosts,
you can make sure that your system operates at optimal performance. By
defining a memory limit for some users submitting jobs to a particular queue
and a specified set of hosts, you can prevent these users from using up all the
memory in the system at one time.
For limits to apply, the job must specify resource requirements (bsub -R
rusage string or RES_REQ in lsb.queues). For example, the a memory
allocation limit of 4 MB is configured in lsb.resources:
Begin Limit
NAME = mem_limit1
MEM = 4
End Limit
A is job submitted with an rusage resource requirement that exceeds this limit:
% bsub -R"rusage[mem=5]" uname
and remains pending:
% bjobs -p 600
JOBID USER STAT QUEUE FROM_HOST EXEC_HOST JOB_NAME SUBMIT_TIME
600 user1 PEND normal suplin02 uname Aug 12 14:05
Resource (mem) limit defined cluster-wide has been reached;
A job is submitted with a resource requirement within the configured limit:
% bsub -R"rusage[mem=3]" sleep 100
is allowed to run:
% bjobs
JOBID USER STAT QUEUE FROM_HOST EXEC_HOST JOB_NAME SUBMIT_TIME
600 user1 PEND normal hostA uname Aug 12 14:05
604 user1 RUN normal hostA sleep 100 Aug 12 14:09
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Administering Platform LSF