IBM LoadLeveler for AIX 5L: Using and Administering

llmodify - Change attributes of a submitted job step

Purpose

Changes the attributes or characteristics of a submitted job.

Syntax

llmodify { -? | -H | -v | [-q] { -x <execution_factor> | -c <consumable_cpus> | -m <consumable_real_memory>} <jobstep> }

Flags

-?

Provides a short usage message.

-H

Provides extended help information.

-v

Outputs the name of the command, release number, service level, service level date, and operating system used to build the command.

-q

Specifies quiet mode: print no messages other than error messages.

-x <execution_factor>

For Gang scheduling only, specifies the execution factor value. Valid values are 1 through 3 and 99.

• 99 - puts the job step into non-preemptable state. All other jobs running on the same nodes will be preempted until this job finish running.
• 1 to 3 - specifies the relative share of CPU time the job step will receive when Gang scheduling is used.

-c <consumable_cpus>

Specifies the consumable CPU value.

Allows the ConsumableCpus resource requirement to be reset to the specified value. This value can be any integer equal or greater than zero (0) and should follow the rules for the resources keyword in the job command file. A value of zero (0) indicates that all previous resource requirements will be removed. It is not possible to literally request zero (0) resources.

-m <consumable_real_memory>

Specifies the consumable real memory value.

Allows the ConsumableMemory resource requirement to be reset to the specified value. No units should be specified, as megabytes (MB) is assumed. This value can be any integer equal or greater than zero (0) and should follow the rules for the resources keyword in the job command file. A value of zero (0) indicates that all previous resource requirements will be removed. It is not possible to literally request zero (0) resources.

jobstep

Is the name of a job step to be modified using the form of host.jobid.stepid

• host : The name of the schedd machine to which the job was submitted. The default is the local machine.
• jobid : The ID assigned to the job when it was submitted using the llsubmit command. A jobid is required.
• stepid : The step ID assigned to the job when it was submitted using the llsubmit command. A stepid is required.

Description

To determine if the request was successful, issue the llq -x -l command and check the resource requirement variable.

The following comments apply to the -x option (execution factor):

• Only LoadLeveler administrators have authority to use this option
• A job step must be in the "Running" state before the execution factor can be set to 99 (prevents the job step from being preempted)
• When you set the execution factor of a job step to 99, all other jobs sharing nodes with the job step are preempted until the job step finishes or the execution factor is lowered

The initial value of execution_factor for a job step is the value specified for its job class. This command will override the class value for a specific job step.

The following comments apply to the -c and -m options (consumable CPUs and consumable real memory):

• Can be used by either the LoadLeveler administrator or the job step owner
• A job step must be in one of the following states:
  • Idle
  • Deferred
  • User Hold
  • System Hold
  • Not Queued
  • Vacate
  • Vacate Pending
  • Rejected
  • Reject Pending
• At the time that the job step is modified, LoadLeveler does not check to make certain that the modified values for resource requirements can be met.

Examples

This example puts the job step c163n07.12.0 into a non-preemptable state and preempts all other job steps running on the same nodes:

llmodify -x 99 c163n07.12.0

This example requests that the execution factor of job step c163n07.12.0 be changed to 3:

llmodify -x 3 c163n07.12.0

Results

The following shows a sample system response for llmodify -x 3 c163n07.12.0:

llmodify: request has been sent to LoadLeveler.

llmodify returns the following exit values:

• 0 (success)
• -1 (error)