Mark R. Fahey

Deploying Darter - A Cray XC30 System

The University of Tennessee, Knoxville acquired a Cray XC30 supercomputer, called Darter, with a peak performance of 248.9 Teraflops. Darter was deployed in late March of 2013 with a very aggressive production timeline - the system was deployed, accepted, and placed into production in only 2 weeks. The Spring Experiment for the Center for Analysis and Prediction of Storms CAPS largely drove the accelerated timeline, as the experiment was scheduled to start in mid-April. The Consortium for Advanced Simulation of Light Water Reactors CASL project also needed access and was able to meet their tight deadlines on the newly acquired XC30. Darters accelerated deployment and operations schedule resulted in substantial scientific impacts within the research community as well as immediate real-world impacts such as early severe tornado warnings [1].

Community use of XALT in its first year in production

XALT collects accurate, detailed, and continuous job-level and link-time data and stores that data in a database; all the data collection is transparent to the users. The data stored can be mined to generate a picture of the compilers, libraries, and other software that users need to run their jobs successfully, highlighting the products that researchers use. We showcase how data collected by XALT can be easily mined into a digestible format by presenting data from four separate HPC centers. XALT is already used by many HPC centers around the world due to its usefulness and complementariness to existing logs and databases. Centers with XALT have a much better understanding of library and executable usage and patterns. We also present new functionality in XALT - namely the ability to anonymize data and early work in providing seamless access to provenance data.

Theta: Rapid installation and acceptance of an XC40 KNL system

In order to provide a stepping stone from the Argonne Leadership Computing Facilitys (ALCF) world class production 10 petaFLOP IBM BlueGene/Q system, Mira, to its next generation 200 petaFLOPS 3rd generation Intel Xeon Phi system, Aurora, ALCF worked with Intel and Cray to acquire an 8.6 petaFLOPS 2nd generation Intel Xeon Phi–based system named Theta. Theta was delivered, installed, integrated, and accepted on an aggressive schedule in just over 3 months. We will detail how we were able to successfully meet the aggressive deadline as well as lessons learned during the process.

Library Function Tracking with XALT

XALT is a tracking tool that collects accurate, detailed, and continuous job-level and link-time data. XALT stores that data in a database and ensures that all the data collection is transparent to the users. XALT tracks libraries and object files linked by the application. A recent feature improvement in XALT enable it to also track external subroutines and functions called by an application. This paper describes the function-tracking implementation in XALT and showcases the kind of data and analysis that becomes available from this new feature. A recently developed web-based interface to XALT database is also described, allowing the staffs of a supercomputing center to more easily understand software usage on their compute resources.

Understanding the Software Needs of High Performance Computer Users with XALT

To access and download xalt data and metadata, please highlight the link and paste it into your address bar: http://web.corral.tacc.utexas.edu/XALT/ . In order to accommodate the anticipated growth over time for this data set, the data is not hosted at this location. The description of the data elements, copy of the CC-BY license, catalogue metadata file, and a listing of the software libraries at time of initial publication are available for download.

A leap forward with UTK's Cray XC30

This paper shows a significant productivity leap for several science groups and the accomplishments they have made to date on Darter - a Cray XC30 at the University of Tennessee Knoxville. The increased productivity is due to faster processors and interconnect combined in a new generation from Cray, and yet it still has a very similar programming environment as compared to previous generations of Cray machines that makes porting easy.

A tale of two systems: flexibility of usage of Kraken and Nautilus at the National Institute for Computational Sciences

The National Institute for Computational Sciences (NICS) at the University of Tennessee currently operates two computational resources for the eXtreme Science and Engineering Discovery Environment (XSEDE), Kraken, a 112,896-core Cray XT5 for general purpose computation, and Nautilus, a 1,024-core SGI Altix UV 1000 for data analysis and visualization. We analyze a years worth of accounting logs for Kraken and Nautilus to understand how users take advantage of these two systems and how analysis jobs differ from general HPC computation We find that researchers take advantage of the flexibility offered by these systems, running a wide variety of jobs at many scales and using the full range of core counts and available memory for their jobs. The jobs on Nautilus tend to use less walltime and more memory per core than the jobs run on Kraken. Additionally, researchers are more likely to run interactive jobs on Nautilus than on Kraken. Small jobs experience a good quality of service on both systems. This information can be used for the management and allocation of time on existing HPC and analysis systems as well as for planning for deploying future HPC and analysis systems.