Following steps for configuring Maui for pre-emption:
SETTING OF PRE-EMPTION ENVIRONMENT
PREEMPTIONPOLICY :
The PREEMPTPOLICY policy has two possible options, namely –
RE-QUEUE - This terminates the job and re-queues the job
SUSPEND - This suspends the job and restarts it once the job that causes the pre-emption completes
PREEMPTPOLICY suspend/requeue
Pre Emptor’s and PREEMPTEE’s :
Queues can be either be a preemptor (i.e., a queue whose jobs can preempt others) or a preemptee (i.e., a queue whose jobs can be preempted) but not both.
You can define one queue as a preemptor and several as preemptee’s or several queues as preemptor’s and one as a preemptee.It can be done by using QOSCFG.
QOSCFG :
In order to configure premption activate the QOSWEIGHT, to do this set the variable QOSWEIGHT to a number greater than 1.
QOSWEIGHT 10
QOSCFG parameters to define which queues are preemptors and which are preempteed
QOSCFG[high] QFLAGS=PREEMPTOR QOSCFG[low] QFLAGS=PREEMPTEE QOSCFG[default] QFLAGS=PREEMPTEE
CLASSCFG :
Once you have defined which queues are preemptors and which are preemptees you can use the CLASSCFG to define priorities. As with the QOSCFG options you need to turn on the CLASSCFG options by setting the CLASSWEIGHT
CLASSWEIGHT 10 You then define CLASSCFG options for each QUEUE and define a priority and associate a QOSCFG with each CLASSCFG using the QDEF parameter CLASSCFG[high] QDEF=high PRIORITY=1100 CLASSCFG[low] QDEF=low PRIORITY=1000 CLASSCFG[default] QDEF=default PRIORITY=900
Checking Preemption Works :
There are two ways through which we can check the preemption :
- Using command
showconfig | less
check that the number PREEMPTOR and PREEMPTEES in the configuration is the same as the
number in the maui.cfg file.2.
The second check is to load the preemptee queue(s) and the submit jobs into the pre-emptor queue
and check that the jobs in the preemptee queue(s) are suspended and restarted once the jobs in
the preemptor queues complete.
NOTE: With priorities the higher the number, the higher the priority
