[torquedev] nodes, procs, tpn and ncpus

Ken Nielson knielson at adaptivecomputing.com
Fri Jun 11 13:24:15 MDT 2010

On 06/11/2010 12:19 PM, "Mgr. Šimon Tóth" wrote:
> On 11.6.2010 18:41, Martin Siegert wrote:
>> It all depends on whether we want to break the meaning of nodes=N being
>> totally equivalent to nodes=N:ppn=1.
>> 1) if we stick to the meaning of nodes=N just being a shorthand for
>>     nodes=N:ppn=1 then -l nodes=4+procs=4 makes just as much sense as
>>     nodes=4:ppn=2+procs=6, i.e., there is no problem.
>> 2) if we change the meaning of nodes=N to become "give me exclusive
>>     access to N nodes" then we need to define what -l nodes=N+procs=M
>>     means.
>> I actually vote for (1). E.g., what is the default if neither nodes nor
>> procs is specified? Currently that is nodes=1:ppn=1, i.e., the default
>> for nodes is 1 and the default for ppn is one. That logical extension is
>> that if only nodes is specified then the default value for ppn should be
>> used. I.e., nodes=N means nodes=N:ppn=1.
>> But that leaves us with the problem of how to specify exclusive access
>> to a node. What about a keyword ALL as in nodes=4:ppn=ALL ? It is a
>> logical extension of the current syntax and is easy to understand.
>> And then things like -l nodes=1:ppn=ALL+procs=42 make total sense
>> (at least to me).
> That's not good enough. How do you tell Torque that you want at least a
> 4 CPU node, but when you get it, then you want all the CPUs?
How about just add #exclusive or other appropriate keyword.


More information about the torquedev mailing list