HP XC System Software Administration Guide Version 4.0

Table 15-1 SLURM Configuration Settings (continued)
Default Value*Setting
'slurm'SlurmUser
All compute nodes, plus 'Procs=2'NodeName
'lsf RootOnly=YES Shared=FORCE Nodes=compute_nodesPartitionName
switch/elan for systems with the Quadrics interconnect
switch/none for systems with any other interconnect
SwitchType
* Default values can be adjusted during installation.
You can also use the scontrol show config command to examine the current SLURM
configuration.
The following general parameters are configured:
• The MaxJobCount parameter is based on the number of CPUs in the HP XC system and
the number of preemption queues to be used in LSF to ensure that allocations are available
for LSF jobs. The default value is 2000 jobs.
• The MinJobAge is set to a value (1 hour or greater) that provides LSF enough time to obtain
job status information after it finishes. The default value is 300 seconds. A value of zero
prevents any job record purging.
• The ReturnToService is set to 1, so that a DOWN node becomes available for use on
registration. The default value is 0, which means that a node will remain in the DOWN state
until you explicitly change its state (even if the slurmd daemon registers and resumes
communications).
The lsf partition is required by LSF with SLURM to identify the nodes available for its
management. The RootOnly setting ensures that only the superuser (root) can request use of
these nodes; LSF with SLURM daemons are run by root. The Shared=FORCE setting enables
LSF with SLURM to dispatch more than one job to a node in this partition and to facilitate
preemption and the efficient use of the resources for serial (single processor) jobs.
NOTE: The Shared=FORCE setting enables LSF HPC to allocate more than one job to a node
if all the jobs are serial jobs or if one parallel job is preempting another parallel job on the same
nodes.
The spconfig command works in conjunction with the cluster_config utility to configure
SLURM for HP XC. The spconfig command is run after all the nodes in the HP XC system are
up and running. The spconfig command performs three main functions:
• It configures an elanhosts configuration file for use by SLURM ELAN support for systems
with a Quadrics interconnect.
• It accurately configures the Procs and RealMemory settings in the slurm.conf file for
all the compute nodes. This data is not known until the compute nodes are booted and are
registered with the HP XC database.
• It restarts SLURM across the HP XC system.
Although a number of options are available, after the cluster_config utility and the spconfig
command execute, the slurm.conf file is generally set up to perform optimally on an HP XC
system. However, you might want to change the node characteristics or the assignment of nodes
to partitions to suit your site needs. The following sections describe some of these common
configuration changes to the slurm.conf file.
15.2 Configuring SLURM 171