LSF Version 7.3 - Platform LSF Configuration Reference

With eexec enabled
The following are some of the things that you can use an eexec to do:
•
Set up the user environment variables on the execution host
•
Monitor job state or resource usage
•
Receive data from stdout of esub
•
Run a shell script to create and populate environment variables needed by jobs
•
Monitor the number of tasks running on a host and raise a flag when this number exceeds a pre-determined limit
•
Pass DCE credentials and AFS tokens using a combination of esub and eexec executables; LSF functions as a pipe
for passing data from the stdout of esub to the stdin of eexec
An eexec can change the user environment variable values transferred from the submission host so that the job runs
on the execution host with a different environment.
For example, if you have a mixed UNIX and Windows cluster, the submission and execution hosts might use different
operating systems. In this case, the submission host environment might not meet the job requirements when the job
runs on the execution host. You can use an eexec to set the correct user environment between the two operating
systems.
Typically, an eexec executable is a shell script that creates and populates the environment variables required by the
job. An eexec can also monitor job execution and enforce site-specific resource usage policies.
The following are some of the things that you can use an eexec to do:
•
Set up the user environment variables on the execution host
•
Monitor job state or resource usage
•
Receive data from stdout of esub
•
Run a shell script to create and populate environment variables needed by jobs
•
Monitor the number of tasks running on a host and raise a flag when this number exceeds a pre-determined limit
•
Pass DCE credentials and AFS tokens using a combination of esub and eexec executables; LSF functions as a pipe
for passing data from the stdout of esub to the stdin of eexec
If an eexec executable exists in the directory specified by LSF_SERVERDIR, LSF invokes that eexec for all jobs
submitted to the cluster. By default, LSF runs eexec on the execution host before the job starts. The job process that
invokes eexec waits for eexec to finish before continuing with job execution.
Unlike a pre-execution command defined at the job, queue, or application levels, an eexec:
•
Runs at job start, finish, or checkpoint
•
Allows the job to run without pending if eexec fails; eexec has no effect on the job state
•
Runs for all jobs, regardless of queue or application profile
Feature: External job submission and execution controls
70 Platform LSF Configuration Reference