Hi Laurent,
Le 06/07/2016 à 11:18, Laurent Facq a écrit :
Hi everybody,
i wonder how slurm choose nodes to allocate ? and how can we change this ?
The resources are choosed by the select plugin. There are several
plugins, each one having its own logic. On a beowulf cluster, you should
either use select/cons_res or select/liner in some cases though.
my problem is that i have ~80 nodes on one cluster :
1-40 have a special feature (OPA - Ominpath+infiniband)
41-80 are standard node (IB InfiniBand only)
i would like to use only one partition with the 80 nodes,
and that users who need OPA nodes could add a constraint "OPA+IB" to
choose OPA+IB nodes
and, that users who dont need OPA are given IB nodes if some are free,
and OPA+IB nodes ONLY if no more IB are free.
the goal is to do a best effort to reserve the OPA nodes to users who
need them.
i thought that if slum search free nodes from 1 to n, putting the OPA+IB
node first in the numbering would do the trick,
but it seems a little bit more complicated.
any idea ?
Yes, you might check-out Weight nodes parameter:
" Weight
The priority of the node for scheduling purposes. All things being
equal, jobs will be allocated the nodes with the lowest weight which
satisfies their requirements. [...]"
Set lower weight on the standard nodes and you win.
Best,
Rémi
