Allocations Guide
Last update: March 21, 2023

TACC enables the research and education of the computational science community at UT and its partners by providing access to advanced computing technologies. TACC's unique and valuable resources include high-performance computing, scientific visualization and data storage systems. The policies and procedures we have implemented to ensure a fair and efficient allocation of these resources are described below.

All TACC resources are allocated on a project basis to a single principal investigator (PI). Faculty, postdoctoral researchers, and research staff can serve as TACC project PIs. Graduate and undergraduate students should have their advisor assume the responsibilities of project PI and submit the allocations request.


Allocations on TACC resources are available to faculty and staff at UT Austin, UT System, TACC Partner Institutions, Texas higher educational institutions and to US academic researchers through the NSF-funded ACCESS or Frontera projects. Eligible UT Austin, UT System, TACC Partner, and Texas higher education users can request access via TACC allocations, ACCESS allocations, or Frontera allocations. All other US academic researchers must request access via either ACCESS allocations or Frontera Allocations.

The TACC industrial affiliates program, Science and Technology Affiliates for Research (STAR), also provides allocations on TACC resources.

Applying for an Allocation

The new TACC Resource Allocation System (TxRAS) will handle all allocation requests for Frontera, Longhorn, Lonestar6 and all future TACC resources. Submit Stampede2 and Maverick2 allocation requests as usual via the TACC User Portal's Project Management page. The project PI or project delegate may add other members of their research group to the allocation via the TACC User Portal.

The PI is responsible for ensuring that all users on the allocation use TACC resources in accordance with the TACC's Acceptable Use Policies.
Failure to do so can result in immediate cancellation of the allocations and account suspension.

All users should familiarize themselves with TACC's Compute Resource User Guides and User Services documentation to learn about the resources best suited to your computational needs.

Allocation/Project Types

TACC offers three types of project allocations: Startup, Educational, and Research. You can request Startup and Educational allocations at any time throughout the year. Research allocation requests are reviewed quarterly by committee. See Applying for an Allocation above.

Startup Allocations

Startup projects are meant to provide the PI with an adequate allocation to build a case for a Research or Educational project. Startup projects will typically receive small allocations with short durations. PIs can apply for a Startup project allocation at any time.

Educational Allocations

Educational project allocations support academic classes, with limited allocation sizes and only on certain TACC resources. Educational project allocations will last for the duration of the class plus 14 days.

Research Allocations

Research project allocations support the computational needs of the scientific community. Research project allocations begin on calendar quarters, are normally for one year, and must be renewed annually for multi-year projects. Requests for new research allocations and renewals must be submitted 30 days prior to the start of the allocation period. Requests submitted after the due date will be considered for the next allocation period. PIs can apply for startup project allocations until the next research project quarterly deadline.

Required Document for Lonestar6, Frontera and Longhorn Requests

NEW: TxRAS now requires further documentation for allocation requests on Frontera, Longhorn and Lonestar6. Each PDF document shall contain 2 sections, with a maximum of 4 pages:

  • Project Description

    A description of the research being performed and how computational resources will impact this research.

  • Resource Justification/Computational Plan

    Describe the scientific applications to be used, and an estimated plan or table justifying the number of requested node-hours, e.g. "We will run 40 jobs using 20 nodes that take about 22 hours to complete".

Example Lonestar6 Allocation Request

Please examine this well-written example Lonestar6 allocation request containing the Project Description and Computational Plan..

Research Allocation Request Deadlines

Research allocation requests are reviewed four times per year according to the following schedule of deadlines.

Allocation Period New/Renewal Request Due By
January 1 - December 31 December 1
April 1 - March 31 March 1
July 1 - June 30 June 1
October 1 - September 31 September 1

Allocation Project Limits

When applying for an allocation on an HPC or Viz system, you will be asked to estimate the number of service units (SUs) you will require for the project. SUs are calculated based on the wall-clock time of your jobs (measured in hours) and the number of nodes, depending on the system, used to run a job. Each job run on the resource consumes the SUs allocated to a project.

All the TACC resources listed below calculate Service Units (SUs) in terms of node-hours. Specialty nodes, such as GPU's, may be charged an additional multiplier.

SUs charged = (Number of nodes) X (job wall-clock time) X (multiplier).

Table 2. Allocation Request Limits per Project type

The following table outlines request limits per resource for various types of allocations.

TACC Resource Startup Project
Educational Project
Research Project
Stampede2 2,100 SUs 2,100 SUs 21,000 SUs
Lonestar6 500 500 Up to 100,000 based on justification
Maverick2 200 200 2,100
Frontera CPU nodes: 5,000 SUs
GPU nodes: 3,000 SUs
(3x multiplier)
See Frontera allocations
Longhorn 600
(6x multiplier)

Scientific Visualization and Analysis

Each TACC large-scale system allocation has access to visualization and analysis resources on that system, including remote desktops (VNC and DCV), Jupyter notebooks and RStudio. These resources can be accessed using command-line scripts (typically found in /share/doc/slurm) or through the TACC Analysis Portal.

TACC operates a production visualization laboratory (vislab) on the main campus of UT Austin in the Peter O'Donnell building (POB lab) and an experimental vislab at TACC's main office complex at the UT Pickle Research Campus (ACB lab). While you do not need a separate allocation to use the vislab, we ask that new users complete a training session on lab use. Users may schedule training and POB lab reservations via the Vislab Reservation page. The ACB lab is intended for exploratory and prototype visualization work. Submit a consulting ticket if you are interested in working with the ACB lab.

Data Storage

All users of active projects automatically receive an allocation of 2 TB and 50 thousand files on the TACC's data archive system (Ranch), and a 1TB allocation on the Stockyard (/work) global file system. We do not grant requests for increase on these individual allocations; however, you may request a larger common allocation for your project through the TACC portal request process. Researchers are encouraged to request a formal Ranch allocation if they plan to use Ranch for anything other than small-scale backup of working files.

To use Corral, you must submit a request through the TACC portal for the appropriate resource, either "Corral" for most normal research needs, or "Corral-Secure" for data that is subject to special restrictions. For each 5TB of allocated space on Corral, there is also a limit of 1 million files. Please note that Corral-Secure allocations require additional documentation to ensure that appropriate protections and agreements are in place. You can initiate that process via the form on the Protected Data Service page. Consult the Corral User Guide for more details on storage limitations, costs and protected data types.

You must request the amount of storage required over the life of your project allocation - you may request an allocation increase partway through the allocation period but these must be independently reviewed and approved. Note that each of these allocation types includes limits on both file count and total size, as these are separate limited resources within each system. All TACC storage allocations last for one year by default, and you will need to plan to renew annually for multi-year projects. Also note that allocation quantities are not cumulative. You must ask for the amount you need each year; asking for 5TB in year one and 5TB in year 2 results in an allocation of 5TB in year 2, not 10TB.