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IQSS: Specify Resources for Containerized FAS-RC Remote Desktop on CANNON or FASSE

The dashboards on CANNON and FASSE let you run Containerized FAS-RC Remote Desktop.  This document covers the resources that are specific to the application.

For information about the resources that are common to any application (Partition, Memory, Cores, runtime, and GPUs), please see IQSS: How to Specify Resources and Choose a Cluster Partition.

Getting Started tip:  The settings you specified the last time you launched the application are saved and appear as “defaults” when you return to the page.


What Does Containerized Mean?  What is a Container?

Instead of loading individual products onto a ship, companies load them into cargo containers which are loaded onto the ship.  One ship can carry many cargo containers from many different companies.  Every container is isolated from all the others and protected from having anything added or removed while on the ship.

Containerized FAS-RC Remote Desktop does something similar for users of CANNON and FASSE.  In this case, the container holds the applications and data you need for your research.  (You might use a container that is provided to you or build your own.)  The clusters can run many containers from many users.  Each container is isolated from all the others and protected from external changes.  This helps ensure that your results are reproducible.

Containers and Virtual Machines (VMs) have similarities and differences – too many to go into here.  Generally speaking, containers require fewer resources than VMs.  Containers can be moved from computer to computer, such as from your own computer to the cluster.

Do I Need to Care That Remote Desktop is Containerized?

CANNON and FASSE use the Singularity container system (see Singularity on the cluster) so you only need to care that Remote Desktop is containerized if you intend to run Singularity during the session.

The launch page includes this message:

IMPORTANT: Please note that it would not be possible to run singularity inside this application. If you need to run singularity please select the regular non containerized remote desktop application.

If you need to use a Singularity container, choose FAS-RC Remote Desktop from the Interactive Apps pull-down menu.

If you are not using a container during your session, it doesn’t matter which Remote Desktop application you launched.

Cluster resources that are specific to Containerized FAS-RC Remote Desktop

Here are the cluster resource options and any IQSS “Getting Started” recommendations for Containerized FAS-RC Remote Desktop:


The Resolution option is only available on CANNON.

Specify the size of the GUI (Graphical User Interface) — width and height — in pixels (“px”).


Getting Started tip:  A width of 1024 and a height of 768 are a reasonable place to start.  If your display/monitor is capable of more, feel free to choose higher values.

This article on Wikipedia lists historical and common display resolutions.

Number of MPI Tasks

Parallel applications can use the Message Passing Interface (MPI) to communicate among themselves whether the component parts are running on multiple cores within a single node or are running on multiple, separate nodes.  If you are using (or writing) a parallel application, you’ll know it.  If you don’t know, you’re not and you can safely leave this set to 1.

Number of MPI Tasks

Getting Started tip:  Leave this set to 1 unless you’re certain your job will take advantage of MPI.

CentOS Version

CentOS Linux is the operating system provided in the Remote Desktop session.

CentOS Version

The drop-down list gives you access to a number of different versions of CentOS Linux.  Click on the list and choose the one you want.  The dashboard remembers your previous choice so you do not need to take any action if the choice shown is correct for you.
CentOS versions

Getting Started tip:  The drop-down list is sorted with the NEWEST version of CentOS Linux at the top of the list.  That was centos7.9 at the time of this writing.

Custom Desktop Folder

Custom Desktop Folder

Getting Started tip:  This option can be left blank if you don’t understand what it is for.

If you need assistance, contact Support.

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