Big Red II at Indiana University

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For help determining which of IU's research supercomputing systems is best suited to meet your needs, use the UITS Supercomputing Pathfinder.

System overview

Big Red II is Indiana University's main system for high-performance parallel computing. With a theoretical peak performance (Rpeak) of one thousand trillion floating-point operations per second (1 petaFLOPS) and a maximal achieved performance (Rmax) of 596.4 teraFLOPS, Big Red II is among the world's fastest research supercomputers. Owned and operated solely by IU, Big Red II is designed to accelerate discovery in a wide variety of fields, including medicine, physics, fine arts, and global climate research, and enable effective analysis of large, complex data sets (i.e., big data).

Big Red II features a hybrid architecture based on two Cray, Inc., supercomputer platforms. As configured upon entering production in August 2013, Big Red II comprised 344 XE6 (CPU-only) compute nodes and 676 XK7 "GPU-accelerated" compute nodes, all connected through Cray's Gemini scalable interconnect, providing a total of 1,020 compute nodes, 21,824 processor cores, and 43,648 GB of RAM. Each XE6 node has two AMD Opteron 16-core Abu Dhabi x86_64 CPUs and 64 GB of RAM; each XK7 node has one AMD Opteron 16-core Interlagos x86_64 CPU, 32 GB of RAM, and one NVIDIA Tesla K20 GPU accelerator.

Big Red II runs a proprietary variant of Linux called Cray Linux Environment (CLE). In CLE, compute elements run a lightweight kernel called Compute Node Linux (CNL), and the service nodes run SUSE Enterprise Linux Server (SLES).

Although Big Red II is a local resource for use by the IU community, its presence has an important effect on the national cyberinfrastructure ecosystem. By providing IU researchers the same technology, software environment, and hybrid architecture used in national supercomputer resources, such as Blue Waters at the National Center of Supercomputing Applications (NCSA), Big Red II meets relatively modest scientific computing needs locally, allowing larger national supercomputing assets to be efficiently used on challenging compute- and data-intensive projects. Big Red II also helps conserve nationally funded supercomputing assets by providing a powerful hybrid system IU scientists can use to fully optimize and tune their applications before migrating them to an Extreme Science and Engineering Discovery Environment (XSEDE) computational service.

System access

Access is available to IU graduate students, faculty, and staff. Undergraduates and non-IU collaborators must have IU faculty sponsors. For details, see the "Research system accounts (all campuses)" section of Computing accounts at IU.

Once your account is created, you can use your IU username and passphrase to log into Big Red II ( with any SSH2 client. Public key authentication also is permitted; see Set up SSH public-key authentication to connect to a remote system.

  • For enhanced security, SSH connections that have been idle for 60 minutes will be disconnected. To protect your data from misuse, remember to log off or lock your computer whenever you leave it.
  • The scheduled monthly maintenance window for IU's high performance computing systems is the second Sunday of each month, 7am-7pm.

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Available software

For a list of packages available on Big Red II, see Big Red II Modules in the IU Cyberinfrastructure Gateway.

Big Red II users can request software using the HPC software request form.

Setting up your user environment

On the research computing resources at Indiana University, the Modules environment management system provides a convenient method for dynamically customizing your software environment.

For more about using Modules to configure your user environment, see On the research computing systems at IU, how do I use Modules to manage my software environment?

File storage options

For file storage information, see On IU's research systems, how much allocated and short-term storage capacity is available to me?

Before storing data on this system, make sure you understand the information in the Working with data containing PHI section (below).

Data transfer nodes

Big Red II users can improve the efficiency and performance of their data transfers by using the system's dedicated data transfer nodes (DTNs). The DTNs feature hardware components that are tuned to optimize I/O throughput, enabling high-speed data transfers between Research Technologies resources at Indiana University and other remote hosts.

For details, see On Big Red II, how do I use the data transfer nodes to improve the efficiency of my data transfers?

Working with data containing PHI

The Health Insurance Portability and Accountability Act of 1996 (HIPAA) established rules protecting the privacy and security of individually identifiable health information. The HIPAA Privacy Rule and Security Rule set national standards requiring organizations and individuals to implement certain administrative, physical, and technical safeguards to maintain the confidentiality, integrity, and availability of protected health information (PHI).

This system meets certain requirements established in the HIPAA Security Rule that enable its use for research involving data that contain protected health information (PHI). You may use this resource for research involving data that contain PHI only if you institute additional administrative, physical, and technical safeguards that complement those UITS already has in place.

Although PHI is one type of institutional data classified as Critical at IU, other types of institutional data classified as Critical are not permitted on Research Technologies systems. For help determining which institutional data elements classified as Critical are considered PHI, see Which data elements in the classifications of institutional data are considered protected health information (PHI)?

For more, see When using UITS Research Technologies systems and services, what are my legal responsibilities for protecting the privacy and security of data containing protected health information (PHI)?

If you need help or have questions, contact UITS HIPAA Consulting.

Running jobs on Big Red II

The Cray Linux Environment (CLE) provides two separate execution environments for running batch and large interactive jobs:

  • Extreme Scalability Mode (ESM): Applications (e.g., AMBER, OpenFOAM, and NAMD) that are optimized for Cray environments usually will run in the ESM environment. If you compile your own application, you should target the ESM environment first.
  • Cluster Compatibility Mode (CCM): Applications (e.g., MATLAB and Ansys) that are developed to run on standard Linux clusters or single servers can run in the CCM environment. In general, the CCM environment will support any standard Linux application.

For more, see Execution environments on Big Red II at IU: Extreme Scalability Mode (ESM) and Cluster Compatibility Mode (CCM).

Big Red II uses the TORQUE resource manager (based on OpenPBS) and the Moab Workload Manager to manage and schedule jobs. TORQUE job scripts must be tailored specifically for the Cray Linux Environment on Big Red II; see How do I run batch jobs on Big Red II at IU? Moab uses fairshare scheduling to track usage and prioritize jobs. For information on fairshare scheduling and using Moab to check the status of batch jobs, see:

For your application to execute on Big Red II's compute nodes, your batch job script must include the appropriate application launch command (aprun for ESM jobs; ccmrun for CCM jobs). Additionally, for CCM jobs, you must load the ccm module (add module load ccm to your ~/.modules file), and use the -l gres=ccm TORQUE directive in your job script. TORQUE scripts to run batch jobs in other Linux environments, such as Red Hat Enterprise Linux (RHEL) or CentOS, will not work on Big Red II without the proper modifications. If your script's executable line does not begin with the appropriate launch command, your application will execute on an aprun service node, not a compute node, and may likely cause a service disruption for all users on the system. The aprun nodes are shared by all currently running jobs, and are intended only for passing job requests. Any memory- or computationally-intensive jobs running on aprun nodes will be terminated.

For details, see:

Queue information

Each debug queue (debug_cpu and debug_gpu) has a maximum limit of two queued jobs per user. Across all queues, the maximum number of queued jobs allowed per user is 500.

CPU-only jobs

Big Red II has the following queues configured to accept jobs that will run on the 32-core dual-Opteron (CPU-only) nodes:

  • cpu: The routing queue for all "production" jobs; each job is routed, based on its resource requirements, to one of the execution queues (normal, serial, or long)
  • debug_cpu: An execution queue reserved for testing and debugging purposes only

Maximum values for each execution queue are defined in the following table.

32-core dual-Opteron (CPU-only) nodes
Execution queue Cores/node Nodes/job Wall time/job Nodes/user
(normal) * 32 128 2 days 128
(serial) * 32 1 7 days 128
(long) * 32 8 14 days 32
debug_cpu 32 4 1 hour 4
* Do not submit jobs directly to the normal, serial, or long execution queues. Always use the cpu routing queue when submitting jobs for "production" runs. Use the debug queue for testing or debugging purposes only.

CPU/GPU jobs

Big Red II has the following queues configured to accept jobs that will run on the 16-core Opteron/NVIDIA (CPU/GPU) nodes:

  • gpu: The main execution queue for jobs on the CPU/GPU nodes
  • opengl: An execution queue reserved for OpenGL jobs
  • cpu16: An execution queue that lets non-GPU jobs run on the CPU/GPU nodes
  • debug_gpu: An execution queue reserved for testing and debugging CPU/GPU codes

Maximum values for each queue are defined as follows:

16-core Opteron/NVIDIA (CPU/GPU) nodes
Execution queue Cores/node Nodes/job Wall time/job Nodes/user
gpu 16 256 7 days 384
opengl 16 256 7 days 384
cpu16 16 32 7 days 384
debug_gpu 16 4 1 hour 4
To best meet the needs of all research projects affiliated with Indiana University, the High Performance Systems (HPS) team administers the batch job queues on UITS Research Technologies supercomputers using resource management and job scheduling policies that optimize the overall efficiency and performance of workloads on those systems. If the structure or configuration of the batch queues on any of IU's supercomputing systems does not meet the needs of your research project, fill out and submit the Research Technologies Ask RT for Help form (for "Select a group to contact", select High Performance Systems).

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Requesting single user time

Although UITS Research Technologies cannot provide dedicated access to an entire compute system during the course of normal operations, "single user time" is made available by request one day a month during each system's regularly scheduled maintenance window to accommodate IU researchers with tasks requiring dedicated access to an entire compute system. To request such single user time, complete and submit the Research Technologies Ask RT for Help form, requesting to run jobs in single user time on HPS systems. If you have questions, email the HPS team.

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Acknowledging grant support

The Indiana University cyberinfrastructure, managed by the Research Technologies division of UITS, is supported by funding from several grants, each of which requires you to acknowledge its support in all presentations and published works stemming from research it has helped to fund. Conscientious acknowledgment of support from past grants also enhances the chances of IU's research community securing funding from grants in the future. For the acknowledgment statement(s) required for scholarly printed works, web pages, talks, online publications, and other presentations that make use of this and/or other grant-funded systems at IU, see If I use IU's research cyberinfrastructure, what sources of funding do I need to acknowledge in my published work?

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For an overview of Big Red II documentation, see Getting started on Big Red II.

For tutorials on how to effectively use Big Red II's hybrid architecture, see Supercomputing quick start guides.

Support for IU research computing systems, software, and services is provided by various UITS Research Technologies units. For help, see Research computing support at IU.

This is document bcqt in the Knowledge Base.
Last modified on 2017-12-20 15:19:45.

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