Mark R. Fahey, Ph.D.  Senior Technical Staff; Computational Scientist National Center for Computational Sciences Oak Ridge National Laboratory

Current Projects

• Automatic Library Tracking Database
• Design and Implementation of automated third-party software installations
• Running the Scientific Computing Group

Interests

Education

Experience

Nov 2008 - present: Scientific Computing Group Leader, National Institute for Computational Science (NICS), Oak Ridge National Laboratory

Nov 2001 - present: Senior Technical Staff; Computational scientist, National Center for Compuational Science (NCCS), Oak Ridge National Laboratory

Dec 1998 - Oct 2001: Director of Computational Science and Engineering Group and Computational scientist, ERDC Major Shared Resource Center,

Publications and Presentations

Tutorials

Presentations (with no associated paper):

• Tutorial: "Preparing your application for TeraGrid beyond 2010," TeraGrid'09, June 2009, Arlington, VA.
• "XT Parallel I/O," presented at the 2007 NCCS Users Meeting, Oak Ridge, TN.
• High Performance on the Power 4 for Real-World, part 4 presented at Scicomp6, Berkeley, CA, Aug 20, 2002.
• ORNL Power 4 Workshop, presented at UT, July 24-25, 2002.
• Multi-level parallelism: Case studies and lessons learned tutorial, presented at SC2001 with Dan Duffy

• CUG 2010 paper
• TeraGrid 2010 paper
• R. Barrett, S. Ahern, M. Fahey, R. Hartman-Baker, J. Horner, S. Poole, and R. Sankaran, "A Taxonomy of MPI-Oriented Usage Models in Parallelized Scientific Codes," Proceedings of the 2009 International Conference on Software Engineering Research and Practice (SERP'09), Las Vegas, July 2009.
• S. Alam, R. Barrett, M. Bast, M. Fahey, J. Kuehn, C. McCurdy, J. Rogers, P. Roth, R. Sankaran, J.S. Vetter, P. Worley, and W. Yu, "Early Evaluation of IBM BlueGene/P," Proceedings of the IEEE/ACM SC2008 Conference, November 2008.
• J.R. Cary, J. Candy, R.H. Cohen, S. Krasheninnikov, D.C. McCune, D.J. Estep, J. Larson, A.D. Malony, P.H. Worley, J.A. Carlsson, A.H. Hakim, P. Hamill, S. Kruger, M. Miah, S. Muzsala, A. Pletzer, S. Shasharina, D. Wade-Stein, N. Wang, L. McInnes, T. Wildey, T. Casper, L. Diachin, T. Epperly, T.D. Rognlien, M.R. Fahey, J. Cobb, A. Morris, S. Shende, G.W. Hammett, K. Indireshkumar, D. Stotler, A. Yu Pigarov, "First results from core-edge parallel composition in the FACETS project," SciDAC 2008, J. Phys.: Conf. Ser. 125 (2008) 012040 (5pp).
• M.R. Fahey, J. Larkin, J. Adams, "I/O Performance on a Massively Parallel XT3/XT4," Proceedings of the 22nd IEEE Internationl Parallel & Distributed Processing Symposium (IPDPS'08), Miami, April 2008.
• Co-author on "The Cray XT4 Quad-core : A First Look," Proceedings of the 50th Cray User Group (CUG08), Helsinki, May 2008.
• N. Jones, M.R. Fahey, "Design, Implementation, and Experiences of Third-Party Software Administration at the ORNL NCCS," Proceedings of the 50th Cray User Group (CUG08), Helsinki, May 2008.
• S. Alam, R. Barrett, M.R. Fahey, J.A. Kuehn, R. Sankaran, P.H. Worley, and J. Larkin, "Cray XT4: An Early Evaluation for Petascale Scientific Simulation," Proceedings of the ACM/IEEE SC2007 Conference, Reno, NV, November 2007.
• J.R. Cary, et. al, "Introducing FACETS, the Framework Application for Core-Edge Transport Simulations," SciDAC 2007, Boston, MA, June 2007.
• M.R. Fahey and J. Larkin, "Guidelines for Efficient Parallel I/O on the Cray XT3/XT4," Proceedings of the 49th Cray User Group (CUG07), Seattle, WA, May 2007.
• M.R. Fahey and J. Larkin, "Performance of a direct numerical simulation solver for turbulent combustion on the Cray XT3/4," Proceedings of the 49th Cray User Group (CUG07), Seattle, WA, May 2007.
• S. Alam, R.F. Barrett, M.R. Fahey, J.A. Kuehn, O.E. B. Messer, R.T. Mills, P.C. Roth, J.S. Vetter, and P.H. Worley, "An Evaluation of the Oak Ridge National Laboratory Cray XT3," Intl. J. of High Performance Computing Applications, 22(1): 52-80, Spring 2008.
• R. Barrett, S. Alam, M.R. Fahey, B. Messer, R.T. Mills, P.C. Roth, J.S. Vetter, J.B. White III and P.H. Worley, "Evaluation of the Cray XT3 at ORNL: a status report," Proceedings of the 48th Cray User Group (CUG06), Lugano, Switzerland, May, 2006.
• M.R. Fahey and J.B. White III, "Portable Performance Oriented Programming Tutorial," Proceedings of the 48th Cray User Group (CUG06), Lugano, Switzerland, May, 2006.
• J.S. Vetter, S. Alam,T.H. Dunigan, M.R. Fahey, P.C. Roth, J.B. White III and P.H. Worley, "Early Evaluation of the Cray XT3," Proceedings of the ACM/IEEE SC2005 Conference, November, 2005.
• J.S. Vetter, S. Alam, T.H. Dunigan, M.R. Fahey, P.C. Roth, and PH. Worley, "Early Evaluation of the Cray XT3," Proceedings of the 20th IEEE International Parallel & Distributed Processing Symposium (IPDPS'06), April, 2006.
• J. Candy and M.R. Fahey, "GYRO Performance on a Variety of MPP Systems," Proceedings of the 47th Cray User Group Meeting, Albuquerque, NM, May, 2005.
• J.A. Kuehn, S. Studham, J.B. White III, M.R. Fahey, S.M. Carter, and J.A. Nichols, "Leadership Computing at Oak Ridge National Laboratory," Proceedings of the 47th Cray User Group (CUG2005), Seattle, WA, May 2005.
• R.T. Mills, E.F. D'Azevedo, and M.R. Fahey, "Progress towards optimizing the PETSc numerical toolkit on the Cray X1," Proceedings of the 47th Cray User Group Meeting, Albuquerque, NM, May, 2005.
• M.R. Fahey, T.H. Dunigan, J.S. Vetter, and P.H. Worley, "Early Evaluation of the Cray XD1," Proceedings of the 47th Cray User Group Conference, Albuquerque, NM, May, 2005.
• J.S. Vetter, S. Alam, R. Barrett, T.H. Dunigan, M.R. Fahey, J.A. Kuehn, J.B. White, and PH. Worley, "Early Evaluation of the Cray XT3 at ORNL," Proceedings of the 47th Cray User Group Conference, Albuquerque, NM, May, 2005.
• P.H. Worley, T.H. Dunigan, M.R. Fahey, J.S. Vetter and J.B. White, "Comparative Analysis of Interprocess Communication on the X1, XD1, and XT3," Proceedings of the 47th Cray User Group Conference, Albuquerque, NM, May 2005.
• E.F. D'Azevedo, R.T. Mills, and M.R. Fahey, "Vectorized sparse matrix multiply for compressed row storage format", International Conference on Computational Science 2005 (ICCS05), Atlanta, GA, May 2005.
• M.R. Fahey and J. Candy, " GYRO: A 5-D Gyrokinetic-Maxwell Solver," Proceedings of the IEEE/ACM SC2004 Conference, Pittsburg, PA, November 2004.
• M.R. Fahey and J. Candy, " GYRO: Analyzing new physic in record time," Proceedings of the 46th Cray User Group Conference, Knoxville, TN, May, 2004 .
• T.H. Dunigan, M.R. Fahey, J.B. White and P.H. Worley, "Early Evaluation of the Cray X1," Proceedings of the IEEE/ACM SC2003 Conference, Phoenix, AZ, November 2003.
• M.R. Fahey and J.B. White, " DOE Ultrascale Evaluation Plan of the Cray X1", Proceedings of the Cray User Group Conference, Columbus, OH, May 2003.
• M.R. Fahey, "Parallel Schur Decomposition of a complex Hessenberg Matrix", ACM TOMS, Vol 29, Issue 33, September 2003. ORNL Report # P03-116587.
• (with P.H. Worley, T.H. Dunigan, J.B. White, and A.S. Bland) "Early Evaluation of the IBM p690", IEEE/ACM SC2002 Conference, Baltimore, MD, November 2002.
• "New Parallel Routines for Dense Complex Eigenvalue Applications," proceedings of the 10th SIAM Conference on Parallel Processing for Scientific Computing, March 2001.
• (with J. Merle Elson) "Numerical Calculation of Radiation from a Long Antenna Situated on a Phontonic Crystal Substrate," Proceedings of the DoD Users Group Conference, June 2000.
• M.R. Fahey, " Large-Scale Collective Communication and Load-Balancing on Parallel HPC Systems," Proceedings of the DoD Users Group Conference, June 2000.
• C. Breshears, H. Gabb and M.R. Fahey, "Application of Fortran Pthreads to Linear Algebra and Scientific Computing," Proceedings of the Cray User Group, 41st Conference, May 1999.
• (with Z. Bai and G. Golub) "Some Large Scale Matrix Computation Problems," J. of Comp. and Appl. Math., 74 (1996) 71-89.

• Large Scale Molecular Dynamics Simulation
• J.S. Vetter, et. al., "Cray X1 Evaluation Status Report", ORNL/TM-2004/13, 2004.
• "Highly Parallel Linpack on the IBM p690," ORNL Technical Report, ORNL/TM-2002/276, 2002.
• J. Hensley, R. Alter, D. Duffy, M.R. Fahey, L. Higbie, T. Oppe, W. Ward, M. Bullock, J. Becklehimer, "Minimizing Runtime Performance Variation with Cpusets on the SGI Origin 3800," PET Preprint TR 01-32, ERDC MSRC, October, 2001.
• M.R. Fahey, "New Complex Parallel Eigenvalue and Eigenvector Routines," LAPACK Working Note #153, Aug 2001.
• J. Hensley, D. Duffy, M.R. Fahey, T. Oppe, W. Ward, and R. Alter, "Performance Comparison of SGI Origin 2800 and SGI Origin 3800 on Application Codes," PET Preprint TR 01-05, ERDC MSRC, April, 2001.
• D. Duffy, M.R. Fahey, J. Hensley, R. Fahey, and T. Oppe, "Analysis of HPC Usage: ERDC MSRC," PET Preprint TR 00-36, ERDC MSRC, February, 2001.
• M.R. Fahey, "Large-Scale Collective Communication and Load-Balancing on Parallel HPC Systems," PET Preprint TR 00-10, ERDC MSRC, April, 2000.
• M.R. Fahey, "Locating Floating-Point Exceptions on the SGI Origin2000," PET Preprint TR 00-03, ERDC MSRC, October, 1999.
• M.R. Fahey and D. Nagle, "Cray Fortran Pointers vs. Fortran 90 Pointers and Migrating from the CRAY C90 to the SGI Origin2000," PET Preprint TR 99-12, CEWES MSRC, April, 1999.
• E. Anderson and M.R. Fahey, "Performance Improvements to LAPACK for the Cray Scientific Library," Technical Report, Cray Research Inc. and LAPACK Working Note #126, April 1997. Or Postscript version.

• "Status on the computational aspects of developing a fully gyrokinetic transport code," Transport Taskforce Workshop, April 2007.
• "Large-Scale Collective Communication and Load-Balancing on Parallel HPC Systems," DoD Users Group Conference, June 2000.

• Steady State Gyrokinetic Transport Project (SSGKT)
• Application support in the Scientific Computing Group
• Parallel Schur Decomposition of a complex Hessenberg Matrix, ACM TOMS, Vol 29, Issue 33, September 2003.
• Cheetah MPI performance tests. Quite surprising results.