Administering Platform LSF - SAS

Chapter 27
Load Thresholds
MEM=100/10
SWAP=200/30
translates into a loadSched condition of mem>=100 && swap>=200 and a
loadStop condition of mem < 10 || swap < 30.
Theory ◆ The r15s, r1m, and r15m CPU run queue length conditions are compared
to the effective queue length as reported by lsload -E, which is
normalised for multiprocessor hosts. Thresholds for these parameters
should be set at appropriate levels for single processor hosts.
◆ Configure load thresholds consistently across queues. If a low priority
queue has higher suspension thresholds than a high priority queue, then
jobs in the higher priority queue will be suspended before jobs in the low
priority queue.
Configuring load thresholds at host level
A shared resource cannot be used as a load threshold in the Hosts section of
the lsf.cluster.cluster_name file.
Configuring suspending conditions at queue level
The condition for suspending a job can be specified using the queue-level
STOP_COND parameter. It is defined by a resource requirement string. Only
the select section of the resource requirement string is considered when
stopping a job. All other sections are ignored.
This parameter provides similar but more flexible functionality for loadStop.
If loadStop thresholds have been specified, then a job will be suspended if
either the STOP_COND is TRUE or the loadStop thresholds are exceeded.
Example This queue will suspend a job based on the idle time for desktop machines
and based on availability of swap and memory on compute servers. Assume
cs is a Boolean resource defined in the lsf.shared file and configured in the
lsf.cluster.cluster_name file to indicate that a host is a compute server:
Begin Queue
.
STOP_COND= select[((!cs && it < 5) || (cs && mem < 15 && swap < 50))]
.
End Queue
Viewing host-level and queue-level suspending conditions
The suspending conditions are displayed by the bhosts -l and bqueues -l
commands.
Viewing job-level suspending conditions
The thresholds that apply to a particular job are the more restrictive of the host
and queue thresholds, and are displayed by the bjobs -l command.
Administering Platform LSF 363