Platform LSF Administration Guide Version 6.2

Chapter 28
Running Parallel Jobs
Administering Platform LSF
433
Specifying a Minimum and Maximum Number of
Processors
When submitting a parallel job, you can also specify a minimum number and a maximum
number of processors.
If you specify a maximum and minimum number of processors, the job will start as soon
as the minimum number of processors is available, but it will use up to the maximum
number of processors, depending on how many processors are available at the time.
Once the job starts running, no more processors will be allocated to it even though more
may be available later on.
Jobs that request fewer processors than the minimum PROCLIMIT defined for the
queue to which the job is submitted, or more processors than the maximum
PROCLIMIT cannot use the queue and are rejected. If the job requests minimum and
maximum processors, the maximum requested cannot be less than the minimum
PROCLIMIT, and the minimum requested cannot be more than the maximum
PROCLIMIT.
If
PARALLEL_SCHED_BY_SLOT=Y in lsb.params, the job specifies a maximum and
minimum number of job slots instead of processors.
Syntax
bsub -n min_proc [ ,max_proc ]
Example
% bsub -n 4,16 myjob
At most, 16 processors can be allocated to this job. If there are less than 16 processors
eligible to run the job, this job can still be started as long as the number of eligible
processors is greater than or equal to 4.