Platform LSF Administration Guide Version 6.2

Automatic Detection of Hardware Reconfiguration
Administering Platform LSF
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How dynamic hardware changes affect LSF
LSF uses ncpus, maxmem, maxswp, maxtmp to make scheduling and load decisions.
When processors are added or removed, LSF licensing is affected because LSF licenses
are based on the number of processors.
If you put a processor offline:
◆ Per host or per-queue load thresholds may be exceeded sooner. This is because LSF
uses the number of CPUS and relative CPU speeds to calculate effective run queue
length.
◆ The value of CPU run queue lengths (r15s, r1m, and r15m) increases.
◆ Jobs may also be suspended or not dispatched because of load thresholds.
◆ Per-processor job slot limit (PJOB_LIMIT in lsb.queues) may be exceeded
sooner.
If you put a new processor online:
◆ Load thresholds may be reached later.
◆ The value of CPU run queue lengths (r15s, r1m, and r15m) is decreased.
◆ Jobs suspended due to load thresholds may be resumed.
Per-processor job slot limit (PJOB_LIMIT in
lsb.queues) may be reached later.