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  • Interactive: The ability to assign all or part of a node to a user with shell level access (nodescheduler, qsub -I, etc),  minimal granularity is per NUMA node, finer would be useful.

    • nodescheduler: What is it that we like about nodescheduler over something like qsub -I or srun --pty bash or condor_submit -i
      • It's not tied to any tty so a user can login multiple times from multiple places to their reserved node without requiring something like screen, tmux, or vnc.  It also means that users aren't all going through nmpost-master.
      • Its creation is asynchronous.  If the cluster is full you don't wait around for your reservation to start, you get an email message when it is ready.
      • It's time limited (e.g. two weeks).  We might be able to do the same with a queue/partition setting but could we then extend that reservation?
      • We get to define the shape of a reservation (whole node, NUMA node, etc).  If we just let people use qsub -I they could reserve all sorts of sizes which may be less efficient.  Then again it may be more efficient.  But either way I think nodescheduler it is simpler for our users.
    • Slurm
      • srun --pty bash This logs the user into an interactive shell on a node with defaults (1 core, 1 GB memory)
      • I don't see how Slurm can reserve NUMA nodes so we will have to just reserve X tasks with Y memory.
      • I don't know how to keep Slurm from giving a user multiple portions of the same host.  With Moab I used naccesspolicy=uniqueuser  This prevents the ambiguity of which ssh connection goes to which cgroup.
      HTCondor

      • Can
    • HTCondor
        even do this?
      • condor_submit -interactive can be shortened to just condor_submit -ii This logs the user into an interactive shell on a node with defaults (1 core equivelent, 0.5 GB memory)
      • Could run a sleep job just like we do with Torque and use condor_ssh_to_job which seems to do X11 properly.  We would probably want to make gygax part of the nmpost pool.
    • nodevnc
      • Given the limitation of Slurm and HTCondor and that we already recommend users use VNC on their interactive nodes, why don't we just provide a nodevnc script that reserves a node (via torque, slurm or HTCondor), start a vnc server and then tells the user it is ready and how to connect to it?  If someone still needs/wants just simple terminal access, then qsub -I or srun --pty bash or condor_submit -i might suffice.

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