[GE users] load sensor scaling or how to make a node picked last
dag at sonsorol.org
Thu Feb 5 15:10:46 GMT 2009
Search the docs at http://wikis.sun.com/display/GridEngine/Home or the
mailing list for "seqno" - SGE by default sorts all suitable queue
instances by load and picks the "least busy" machine from among the
You can override/influence this behavior by switching to seqno-based
sorting where you can rank your machines with an integer number that
is used in the sort.
If you tag all your new machines with a seqno of "0" and your older
machines with a "1" then you'll find that the SGE scheduler will
preferentially bias itself towards then newer machines.
Another option is to play games with adjustments to reported load
averages. SGE will artificially spike the reported load average on a
node right after a job lands there so that the scheduler does not slam
an idle node with too much work all at once. By tweaking these numbers
and the length of the delay time you can make your older machines
appear to be busier than they really are. I've played games with that
in the past to avoid certain machines over time.
Anyway, sequence based sorting is what you should look into first.
On Feb 5, 2009, at 10:02 AM, russray wrote:
> I have a SGE6.1 install and it is working well. We have five linux
> machines with all dual or quad cores except for our first machine
> which is an older machine. The install was purely default with no
> changes other than setting up queues for the different type of jobs
> to run. No priorities for users or projects exist.
> I would like to "handicap" the older machine so that it isn't picked
> if no jobs are running. qstat -f shows the load_avg of this machine
> to be 0.00 when no job is running and therefore it is often picked
> over other machines with more memory and cpu speed that have
> load_avg of 0.01 or 0.02. I would like to force a handicap onto the
> slow machine so that it is basically picked almost last. In other
> words, if a job is running on a quad, I would rather have a second
> job start on it than on the slow machine.
> How would I set this? I've been looking through the manual and
> can't seem to find what I need.
To unsubscribe from this discussion, e-mail: [users-unsubscribe at gridengine.sunsource.net].
More information about the gridengine-users