Platform LSF Running Jobs Version 6.2

Suspending and Resuming Jobs (bstop and bresume)

Running Jobs with Platform LSF

Suspending and Resuming Jobs (bstop and bresume)

The bstop and bresume commands allow you to suspend or resume a job.

A job can also be suspended by its owner or the LSF administrator with the

bstop

command. These jobs are considered user-suspended and are displayed by

bjobs as

USUSP.

When the user restarts the job with the

bresume command, the job is not started

immediately to prevent overloading. Instead, the job is changed from

USUSP to SSUSP

(suspended by the system). The

SSUSP job is resumed when host load levels are within

the scheduling thresholds for that job, similarly to jobs suspended due to high load.

If a user suspends a high priority job from a non-preemptive queue, the load may

become low enough for LSF to start a lower priority job in its place. The load created

by the low priority job can prevent the high priority job from resuming.

This can be avoided by configuring preemptive queues. See Administering

Platform LSF for information about configuring queues.

Suspending a job

bstop command

To suspend a job, use the bstop command. Suspending a job causes your job to go into

USUSP state if the job is already started, or to go into PSUSP state if your job is pending.

By default, jobs that are suspended by the administrator can only be resumed by the

administrator or

root; users do not have permission to resume a job suspended by

another user or the administrator. Administrators can resume jobs suspended by users

or administrators. Administrators can also enable users to resume their own jobs that

have been stopped by an administrator.

UNIX

bstop

sends the following signals to the job:

◆

SIGTSTP for parallel or interactive jobs

SIGTSTP is caught by the master process and passed to all the slave processes

running on other hosts.

◆

SIGSTOP for sequential jobs

SIGSTOP cannot be caught by user programs. The SIGSTOP signal can be

configured with the LSB_SIGSTOP parameter in

lsf.conf.

Example

To suspend job 3421, enter:

% bstop 3421

Job <3421> is being stopped