Administering Platform LSF - SAS

About Pre-Execution and Post-Execution Commands
About Pre-Execution and Post-Execution Commands
Pre-execution commands
Post-execution commands
Each batch job can be submitted with optional pre- and post-execution
commands. Pre- and post-execution commands can be any excutable
command lines to be run before a job is started or after a job finishes.
Some batch jobs require resources that LSF does not directly support. For
example, appropriate pre- and/or post-execution commands can be used to
handle various situations:
◆ Reserving devices like tape drives
◆ Creating and deleting scratch directories for a job
◆ Customized scheduling
◆ Checking availability of software licenses
◆ Assigning jobs to run on specific processors on SMP machines
By default, the pre- and post-execution commands are run under the same user
ID, environment, and home and working directories as the batch job. If the
command is not in your normal execution path, the full path name of the
command must be specified.
For parallel jobs, the command is run on the first selected host.
Pre-execution commands support job starting decisions which cannot be
configured directly in LSF. LSF supports both job-level and queue-level preexecution.
The pre-execution command returns information to LSF using its exit status.
When a pre-execution command is specified, the job is held in the queue until
the specified pre-execution command returns exit status zero (0).
If the pre-execution command exits with non-zero status, the batch job is not
dispatched. The job goes back to the PEND state, and LSF tries to dispatch
another job to that host. While the job is pending, other jobs can proceed
ahead of the waiting job. The next time LSF tries to dispatch jobs this process
is repeated.
If the pre-execution command exits with a value of 99, the job will not go back
to the PEND state, it will exit. This gives you flexibility to abort the job if the
pre-execution command fails.
LSF assumes that the pre-execution command runs without side effects. For
example, if the pre-execution command reserves a software license or other
resource, you must not reserve the same resource more than once for the same
batch job.
If a post-execution command is specified, then the command is run after the
job is finished regardless of the exit state of the job.
Post-execution commands are typically used to clean up some state left by the
pre-execution and the job execution. Post-execution is only supported at the
queue level.
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Administering Platform LSF