[slurm-users] Topology configuration questions:

[Prentice Bisbal]

On 01/17/2019 06:36 PM, Ryan Novosielski wrote:
> I don’t actually know the answer to this one, but we have it provisioned to all nodes.
>
> Note that if you care about node weights (eg. NodeName=whatever001 Weight=2, etc. in slurm.conf), using the topology function will disable it. I believe I was promised a warning about that in the future in a conversation with SchedMD.

Well, that's going to be a big problem for me. One of the goals of me 
overhauling our Slurm config is to take advantage of the node weighting 
function to prioritize certain hardware over others in our very 
heterogeneous cluster.

I may have to provide a larger description of my hardware/situation to 
the list and ask for suggestions on how to best handle the problem.

Prentice
>
>> On Jan 17, 2019, at 4:52 PM, Prentice Bisbal <pbisbal at pppl.gov> wrote:
>>
>> And a follow-up question: Does topology.conf need to be on all the nodes, or just the slurm controller? It's not clear from that web page. I would assume only the controller needs it.
>>
>> Prentice
>>
>> On 1/17/19 4:49 PM, Prentice Bisbal wrote:
>>>  From https://slurm.schedmd.com/topology.html:
>>>
>>>> Note that compute nodes on switches that lack a common parent switch can be used, but no job will span leaf switches without a common parent (unless the TopologyParam=TopoOptional option is used). For example, it is legal to remove the line "SwitchName=s4 Switches=s[0-3]" from the above topology.conf file. In that case, no job will span more than four compute nodes on any single leaf switch. This configuration can be useful if one wants to schedule multiple phyisical clusters as a single logical cluster under the control of a single slurmctld daemon.
>>> My current environment falls into the category of multiple physical clusters being treated as a single logical cluster under the control of a single slurmctld daemon. At least, that's my goal.
>>>
>>> In my environment, I have 2 "clusters" connected by their own separate IB fabrics, and one "cluster" connected with 10 GbE. I have a fourth cluster connected with only 1GbE. For this 4th cluster, we don't want jobs to span nodes, due to the slow performance of 1 GbE. (This cluster is intended for serial and low-core count parallel jobs) If I just leave those nodes out of the topology.conf file, will that have the desired affect of not allocating multi-node jobs to those nodes, or will it result in an error of some sort?
>>>