Administering Platform LSF - SAS

Performance Tuning for Interactive Batch Jobs
Performance Tuning for Interactive Batch Jobs
Types of load conditions
Scheduling
conditions
Suspending
conditions
Resuming
conditions
LSF is often used on systems that support both interactive and batch users. On
one hand, users are often concerned that load sharing will overload their
workstations and slow down their interactive tasks. On the other hand, some
users want to dedicate some machines for critical batch jobs so that they have
guaranteed resources. Even if all your workload is batch jobs, you still want to
reduce resource contentions and operating system overhead to maximize the
use of your resources.
Numerous parameters can be used to control your resource allocation and to
avoid undesirable contention.
Since interferences are often reflected from the load indices, LSF responds to
load changes to avoid or reduce contentions. LSF can take actions on jobs to
reduce interference before or after jobs are started. These actions are triggered
by different load conditions. Most of the conditions can be configured at both
the queue level and at the host level. Conditions defined at the queue level
apply to all hosts used by the queue, while conditions defined at the host level
apply to all queues using the host.
These conditions, if met, trigger the start of more jobs. The scheduling
conditions are defined in terms of load thresholds or resource requirements.
At the queue level, scheduling conditions are configured as either resource
requirements or scheduling load thresholds, as described in lsb.queues. At
the host level, the scheduling conditions are defined as scheduling load
thresholds, as described in lsb.hosts.
These conditions affect running jobs. When these conditions are met, a
SUSPEND action is performed to a running job.
At the queue level, suspending conditions are defined as STOP_COND as
described in lsb.queues or as suspending load threshold. At the host level,
suspending conditions are defined as stop load threshold as described in
lsb.hosts.
These conditions determine when a suspended job can be resumed. When
these conditions are met, a RESUME action is performed on a suspended job.
At the queue level, resume conditions are defined as by RESUME_COND in
lsb.queues, or by the loadSched thresholds for the queue if RESUME_COND
is not defined.
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Administering Platform LSF