NERSC HPC Program Requirements Reviews Overview
Scope
These workshops are focused on determining the computational challenges facing research teams and the computational resources scientists will need to meet their research objectives. The goal is to assure that NERSC, the DOE Office of Science, and its program offices, will be able to provide the high performance computing and storage resources necessary to support the Office of Science's scientific goals. The merits of the scientific research are not under discussion in these workshops.
NERSC and DOE are attempting to further understand how high performance computing resources are being used by researchers in the process of scientific discovery and what additional resources (hardware and services) will be required in the next five years to meet research objectives. The collected requirements, along with their science context, are captured in public formal workshop reports.
Note that in this and other documents we use the term "computing requirements" to mean the full complement of needs for effective high-performance scientific computing, including computational and storage systems as well as a full complement of services, including technical consulting, software support, training, and outreach.
Case Studies
The workshops are centered around scientific "case studies." Each case study presents an overview of a scientific research program and its objectives, a description of the computational aspects of the research, and the computational resources that will be required to succesfully conduct the research over the next 3-5 years.
In particular, a case study should answer the following questions:
- What are the scientific objectives today and over the next 3-5 years.
- What process is being modeled by computation or what analysis is being performed?
- What are the computational methods of solution?
- What are the important parameters of the computational model?
- What computational algorithms and applications are important today? How will this change over the next 3-5 years?
- How is the computational size of the problem characterized? How will this change in the next 5 years?
- How is parallelism expressed and what limitations to increased parallelism exist?
- What are the principal computational limitations to accomplishing scientific goals today? What are the expectations over the next 3-5 years?
- What software and services are important to you today and will this change over the next 3-5 years? Are there new or additional software and services that will be needed?
- What aspects of high performance computing most effect your scientific productivity?
Given the emphasis on large-scale computing at NERSC and the trend toward multi- and many-core architectures, a focus is on parallelism - how it is expressed, what limitations might exist, and how are science teams planning to exploit multicore parallelism.
Please see the FAQ page that provides more information for case study authors.
Workshop Process
Workshops are by invitation only and invitations come from the DOE program office.
DOE program managers and NERSC facilitators decide which case studies will be prepared and which workshop participants will lead them.
Case study leaders will be sent a Requirements Case Study Template document prior to the workshop that should be filled out with initial information and returned to the NERSC workshop facilitators no later than the end of the week immediately prior to the workshop.
The workshops typically begin with presentations by NERSC staff and by the DOE program managers. After that, workshop attendees present the case studies in turn, and the science and computational needs are discussed. We ask that case studies be presented via round-table discussions - the interactivity this typically engenders is very valuable and we believe this to be more productive than formal presentations.
After the workshop, attendees update their case study documents with information or clarifications from the workshop. NERSC staff then compile the case studies into a workshop final report, including any material that came out in the workshop that does not fit into one particular case study (e.g. needs or issues that affect all science done by the program). After review by workshop participants, the final report is posted in the HPC Requirements for Science of the NERSC web site.
Other Requirements Gathering
NERSC also gathers information via its ERCAP allocations request process, by monitoring the way its computing and storage systems are used, through the NERSC Users' Group (NUG), and in day-to-day interaction with scientists that use the facility and their DOE program managers.
Data obtained from requirements studies are combined with monitoring of technology trends to help set enterprise-wide objectives for NERSC science-driven systems and services. In other words, these data have a direct impact on NERSC planning and procurements for computing, storage, networking, and visualization platforms as well as the entire range of support activities that enable a broad range of scientists to effectively use NERSC systems in their research.