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Re: [Condor-users] Better control over negotiator?

I'll answer this one 'cause it's what we do and I know the answer.

> Is it possible, in an almost idle pool, to claim slots "in 
> alphabetical 
> order"?

So we fill our machines "width first". If the system is empty jobs start
on all the slot1@<machine> locations then start filling up the
slot2@<machine> locations. That way, in a system with light load, the
jobs get to run on as free a machine as possible. We do this with:

##  The NEGOTIATOR_POST_JOB_RANK expression chooses between
##  resources that are equally preferred by the job.
##  The following example expression steers jobs toward
##  faster machines and tends to fill a cluster of multi-processors
##  breadth-first instead of depth-first.  In this example,
##  the expression is chosen to have no effect when preemption
##  would take place, allowing control to pass on to
- VirtualMachineID)
##  Break ties by looking for machines that have Idle longer than others
##  and use them first. Also try and use faster machines before slower
##  machines and assign jobs to separate machines before we start
##  two jobs on a machine.
ALTERA_NEGOTIATOR_POST_JOB_RANK = (((Activity =?= 'Owner') * (State =?=
'Idle')) * 1000000000) + ((Activity =?= 'Unclaimed') * 100000000) +
(KFlops * 0.001) - (VirtualMachineID * 10)

The second line is the one that's actually used. I just put it all there
for general information.

As for your other question:

> Is there a (simple but consistent) way to handle the small
> slots the same, (by rounding MIPS and KFLOPS values ? while reserving
> the big ones for big jobs as long as possible?

Well, here's our pre-job rank expression for your perusal:

##  The NEGOTIATOR_PRE_JOB_RANK expression overrides all other ranks
##  that are used to pick a match from the set of possibilities.
##  Try running jobs on machines that are unclaimed. Also try putting
##  jobs on machines that are in the state Owner+Idle because these
##  may just have very strict START requirements.
ALTERA_NEGOTIATOR_PRE_JOB_RANK =  (((Activity =?= 'Owner') * (State =?=
'Idle')) * 1000000000) + ((Activity =?= 'Unclaimed') * 100000000)

You could add and inverse KFLOPS or MIPS to that expression. Ditto to
the post rank expression.

- Ian

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