Interactive Sessions

Particularly good for debugging and working with software GUI.

We strongly recommend user check available resources using hpctools - Tufts HPC Helper Tool before starting interactive jobs.

$ srun [options] --pty [command]

• Command

  • command to run an application, given the module is already loaded.

  • bash for a bash shell

• Options

  • Pseudo terminal --pty

  • Partition -p

    • Default batch if not specified

  • Time -t or --time=

    • Default 15 minutes if not specified on non-interactive partition

    • Format: DD-HH:MM:SS

  • Number of CPU cores -n

    • Default 1 if not specified

  • Memory --mem=

    • Default 2GB if not specified

  • GPU --gres=

    • Default none

  • X Window --x11=first

    • Default none

  • Specify node name -w or --nodelist=

    • Job will only be placed on the nodes listed.

    • Optional.

CPU Job

Starting an interactive session of bash shell on preempt partition with 2 CPU cores and 2GB of RAM, with X11 forwarding for 1 day, 2 hours, and 30 minutes (use exit to end session and release resources).

[tutln01@login-prod-01 ~]$ srun -p preempt -t 1-2:30:00 -n 2 --mem=2g --x11=first --pty bash
srun: job 296794 queued and waiting for resources
srun: job 296794 has been allocated resources
[tutln01@cc1gpu001 ~]$ 

Note: If you are requesting X11 forwarding with srun, -XC or-YC or -XYC must be used upon login with ssh.

GPU Job

Starting an interactive session of bash shell on preempt partition with 2 CPU cores and 4GB of RAM, with 1 A100 GPU with 40GB of device memory for 1 day, 2 hours, and 30 minutes (use exit to end session and release resources).

[tutln01@login-prod-01 ~]$ srun -p preempt -t 1-2:30:00 -n 2 --mem=4g --gres=gpu:a100:1 --constraint="a100-40G" --pty bash

Once your resource is allocated on a compute node, use nvidia-smi to check GPU info.