Thread: Running jobs are suspending for unrunnable jobs.

Originally posted by: garym, Wed Nov 29, 2006 8:01 pm

I have a test queue defined that is pre-emptive over all lower priority queues. We have added limits so that only one test 'job' can be run by a user at any one time (where job may be more than one cpu).

I have defined a resource testcount under lsf.cluster.name:

Code:

RESOURCENAME LOCATION 
testcount (0@[all]) 
End ResourceMap

and placed a limit on that resource under lsb.resources:

Code:

Begin Limit 
NAME = testcount_limit 
PER_USER = all 
PER_QUEUE=test 
RESOURCE = [testcount,1] 
End Limit

On the test queue, I have:

Code:

RES_REQ = rusage[testcount=1]

The problem: A user will submit more than one job to the test queue which will suspend other jobs in the cluster, but the test job will pend with the reason:

Code:

Resource (testcount) limit defined on queue has been reached;

Jobs should not be suspended until the next test queue job is able to run. What am I missing?

Originally posted by: Rasheed, Thu Dec 14, 2006 3:21 am

Hi,

Please contact support@platform.com for assistance on this issue and our support engineers will be glad to assist you further.

Platform Support

Originally posted by: ddunlap, Thu Feb 08, 2007 4:11 pm

This is pretty much "after the fact", but here's a little follow up, for general interest:

- when you put "testcount (0@[all])" in lsf.cluster.name, that tells LSF:
"there are 0 instances of the resource 'testcount', shared by all hosts".
In your case, I think you wanted to set this to "1"

- the limit in lsb.resources is not needed. By setting up testcount as a
shared resource, with an initial value of 1, that will enforce the limit --
as long as you set up the queue correctly (which, you almost did)

- in lsb.queues, setting "RES_REQ=rusage[testcount=1]" tells LSF:
"for all jobs that run in this queue, reserve 1 unit of 'testcount' for
the duration of the job". But, you didn't include any selection criteria,
and I think you need that:
RES_REQ="select[testcount>0] rusage[testcount=1]"
This says:
"select only machines that have a value of testcount>0, and reserve
1 unit of testcount for the duration of the job"

On the other hand, there might be an easier way to accomplish the
same thing: in the test queue, set:
QJOB_LIMIT=1

This says "only run one job at a time through the test queue".

My suggestion is: always look for the simplest way to do what you want.

My $.02,
Dale
_________________
Dale Dunlap
Technical Consultant