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Table of Contents

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Note

This document assumes a basic familiarity with the Linux command line. If you are new to Linux, or need a refresher, Research Computing has created a guide at The Linux Shell on the Sol Supercomputer.

Quick Start

For users who have never used a supercomputer before, we recommend reading through the “Detailed Start” section of this document.

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  1. Connect to the ASU Cisco AnyConnect VPN

  2. Login with your ASURITE & password

  3. Choose a connection method (terminal / web portal)

  4. Transfer needed files

  5. Run an interactive session or create an SBATCH script

Important Terms

  • HPC: Short for “High Performance Computing” it refers to a group (or a cluster) of interconnected computers designed for parallelism across many computers at once. Publicly these are often called “supercomputers”.

  • Node: A single machine in a supercomputer. This will be either a physical machine or a virtual machine. 

  • Login Node: A node intended as a launching point to compute nodes. Login nodes have minimal resources and should not be used for any application that consumes a lot of CPU or memory. This is also known as a “head node”.

  • Compute Node: Nodes intended for heavy compute. This is where all heavy processing should be done.

  • Job: Work assigned to be done on a compute node. Any time a compute node is assigned a job is created.

  • Memory (RAM): Short for “Random-Access Memory“. This is used for the amount of memory that each calculation or computation requires in order to execute and complete successfully. The term “memory“ is not used for disk space. This is another main component that defines a node.

  • CPU: Short for “Central Processing Unit”, also called a core. This is one of the main components that defines a computing device, such as a node.

  • GPU: Short for “Graphic Processing Unit”. This is a specialized piece of hardware that can enable and accelerate certain computational research.

  • Scheduler: The application on our end that manages and assigns (allocates) compute resources for jobs. The scheduler used on the ASU Supercomputers is called Slurm.

Detailed Start

Connect through the Cisco VPN

All Research Computing resources require the user to be connected to the ASU Cisco AnyConnect VPN. This is encouraged for all users, regardless if they are on campus or off campus.

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Warning

PLEASE NOTE: If you are having trouble connecting to the ASU VPN you will need tocontact ASU Enterprise Technology. Research Computing cannot assist issues with the VPN.

Choosing a Connection Method

Research Computing provides two methods for connecting to the supercomputer. Each has their advantages and disadvantages.

  1. Connecting to the Supercomputer with the Web Portal
    The web portal has become the standard for new users. It provides a file system viewer and editor, a job submission tool, the ability to view the job queue, and a zoo of interactive applications including a virtual desktop, Jupyter Lab, and RStudio. In the file manager, uploading files is as easy as dragging-and-dropping through the interface! This web portal is accessible through sol.asu.edu.

    The virtual desktop provided by sol.asu.edu is the best way to use graphical applications on the supercomputer. However, please try to avoid using graphical sessions unless you are first learning how to work with the supercomputer or you’re working with software that is only accessible through a graphical user interface. The goal of any interactive session on the supercomputer should be to develop a working /wiki/spaces/RC/pages/1643905055 so that you may properly begin to take advantage of what supercomputing offers.

  2. Connecting to the Supercomputer with SSH
    SSH is the most versatile method. It is ideal for submitting jobs at scale by allowing you to create custom workflows, submit multiple jobs simultaneously through job arrays, and explore options to avoid data loss through dependencies. However, it tends to be slower with interactive graphical applications. If you intend to use MATLAB graphically (as opposed to MATLAB command line only) the screen draw will be very slow. For graphical applications, we recommend our web portal instead.

Login to Sol

You are now ready to reach the login node! The login node is intended as a launching point to allocate compute nodes for your job. You only need to provide your ASURITE and password, if prompted.

Info

The login node is running software called arbiter2. Arbiter2 monitors and protects interactive nodes with cgroups. It records the activity on nodes, automatically sets limits on the resources available to each user, and notifies users and administrators by email when users are penalized for using excessive resources.

Transfer Needed Files

This is optional. However, most research requires data sets or other files to be imported. For details, please see these tutorials on Transferring Files to and from the Supercomputer or using /wiki/spaces/RC/pages/201490433.

Run an Interactive Session or Create an SBATCH Script

If you are using an interactive app provided in the web portal, this section can be skipped. If you are using a personally installed version of RStudio or Jupyter, please continue reading this section.

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  1. Creating an interactive session in the web portal using an interactive app, such as Jupyter, RStudio, or MATLAB. This will assign a compute node to your interactive session in an interactive app of your choice. This is a great option for users to become familiar with using the supercomputer as well as to develop, test, and debug code.

  2. Starting an Interactive Session in the shell. This will assign a compute node and connect your command prompt to it. This is good when working by hand to establish the commands needed to run your work. When your session disconnects, the interactive session also closes. Any unsaved work will be lost.

  3. /wiki/spaces/RC/pages/1643905055. This is a method of telling the scheduler you want an unattended (or non-interactive) job to run. When an sbatch script is submitted, the job will run until it either completes, fails, or runs out of time. These sbatch scripts can be submitted through the shell or through the “Job Composer“ in the web portal.

Recommended Reading

The page linked above will cover additional details on the supercomputer environment which will assist in maximizing your results.

Helpful Tips

If your job is failing, a JobID helps us significantly as we can pull detailed information about the job.

For a great reference on building proficiency with command-line tools, we provide the following MIT link from CSAIL.

Additional Help

If you require further assistance on this topic, please don't hesitate to contact the Research Computing Team. To create a support ticket, kindly send an email to rtshelp@asu.edu. For quick inquiries, you're welcome to reach out via our #rc-support Slack Channel or attend our office hours for live assistance

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