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Analyzing PICL trace data with MEDEA [chapter]

Alessandro P. Merlo, Patrick H. Worley
1994 Lecture Notes in Computer Science  
The Intel iPSC/2 and iPSC/860 systems are distributed memory, h ypercube{connected parallel architectures.  ...  Our experiments on the Paragon also point out the utility o f h a ving portable tools like P I C L and MEDEA.  ... 
doi:10.1007/3-540-58021-2_25 fatcat:yw2vadhumngzdmawhb3kmx66ue

Performance modeling for SPMD message-passing programs

JÜRGEN BREHM, PATRICK H. WORLEY, MANISH MADHUKAR
1998 Concurrency Practice and Experience  
-communication -computation Analytieal model w i t h parameters h+ System description Parameters: -setup time for send -bandwidth mem->buf -bandwidth links -setup time for receive -  ...  N L M H S ) . NLLATS . N L V E R S 40 . NLLATI . NLVERE . (a + b . (NLLONE/2 -NLHMS) 70 . MLLATI . N L V E R E . (a + b . NLLOI?_F/4) 40 . NLLATI NLVERE . (a + b . M L D N E / 2 ) (25/2) NLLATJ .  ... 
doi:10.1002/(sici)1096-9128(19980425)10:5<333::aid-cpe321>3.0.co;2-x fatcat:fbpf54wpkrhzzhtiwrznrfxu3y

Performance evaluation of the IBM SP and the Compaq AlphaServer SC

Patrick H. Worley
2000 Proceedings of the 14th international conference on Supercomputing - ICS '00  
doi:10.1145/335231.335254 dblp:conf/ics/Worley00 fatcat:e5ztmih3p5hchdn23bqqwlio5a

Results of the PERI survey of SciDAC applications

Bronis R de Supinski, Jeffrey K Hollingworth, Shirley Moore, Patrick H Worley
2007 Journal of Physics, Conference Series  
The work of Worley was supported under Contract No. DE-AC05-00OR22725 with UT-Battelle, LLC. Accordingly, the U.S.  ... 
doi:10.1088/1742-6596/78/1/012027 fatcat:gh5bfmksjzgb7n6uupmkfgrr3i

Improving the performance scalability of the community atmosphere model

Arthur A. Mirin, Patrick H. Worley
2011 The international journal of high performance computing applications  
The Community Atmosphere Model (CAM), which serves as the atmosphere component of the Community Climate System Model (CCSM), is currently the most computationally expensive CCSM component in typical configurations. Improving performance scalability in CAM has been a challenge, due largely to algorithmic restrictions necessitated by the polar singularities in its latitude-longitude computational grid. Nevertheless, through a combination of exploiting additional parallelism, implementing improved
more » ... communication protocols, and eliminating scalability bottlenecks, we have been able to more than double the maximum throughput of CAM on production platforms. We describe these improvements and present results on the Cray XT4/XT5, IBM BG/P, and an Opteron/Infiniband cluster. This improved performance will enable the CCSM research community to use its computing resources more effectively, allowing additional and more computationally expensive experiments to be run in support of the upcoming Intergovernmental Panel on Climate Change (IPCC) fifth assessment.
doi:10.1177/1094342011412630 fatcat:guozzwztn5eq5kn5buqqvntizm

Cray XT4

Sadaf R. Alam, Jeffery A. Kuehn, Richard F. Barrett, Jeff M. Larkin, Mark R. Fahey, Ramanan Sankaran, Patrick H. Worley
2007 Proceedings of the 2007 ACM/IEEE conference on Supercomputing - SC '07  
The scientific simulation capabilities of next generation high-end computing technology will depend on striking a balance among memory, processor, I/O, and local and global network performance across the breadth of the scientific simulation space. The Cray XT4 combines commodity AMD dual core Opteron processor technology with the second generation of Cray's custom communication accelerator in a system design whose balance is claimed to be driven by the demands of scientific simulation. This
more » ... r presents an evaluation of the Cray XT4 using microbenchmarks to develop a controlled understanding of individual system components, providing the context for analyzing and comprehending the performance of several petascale-ready applications. Results gathered from several strategic application domains are compared with observations on the previous generation Cray XT3 and other high-end computing systems, demonstrating performance improvements across a wide variety of application benchmark problems.
doi:10.1145/1362622.1362675 dblp:conf/sc/AlamKBLFSW07 fatcat:j644djxenje7zh4uadmmzvkhcq

Performance Portability in the Physical Parameterizations of the Community Atmospheric Model

Patrick H. Worley, John B. Drake
2005 The international journal of high performance computing applications  
AUTHOR BIOGRAPHIES Patrick H. Worley is a senior research computer scientist in the Computer Science and Mathematics Division of ORNL.  ...  , 2000 (Worley, , 2002 Worley et al., 2002) using the CCM column radiation model (CRM; see http://www.cgd.ucar.edu/ cms/crm/), and by numerous reports in the literature on the utility of cache blocking  ...  For the absorptivity and emissivity update, the default is to calculate it during a radiation time step once every 12 h. We refer to this as an "absems" time step.  ... 
doi:10.1177/1094342005056095 fatcat:fwbqxezpx5gmxggelb2aoph374

Performance tuning and evaluation of a parallel community climate model

John B. Drake, Steve Hammond, Rodney James, Patrick H. Worley
1999 Proceedings of the 1999 ACM/IEEE conference on Supercomputing (CDROM) - Supercomputing '99  
The data generated from these experiments can be viewed at http://www.epm.ornl.gov/ e worley/studies/protocol.html The results relevant to this study are as follows. Origin.  ... 
doi:10.1145/331532.331566 dblp:conf/sc/DrakeHJW99 fatcat:kopucokyafa7jdvlx2godpm3im

Description and evaluation of the Community Ice Sheet Model (CISM) v2.1

William H. Lipscomb, Stephen F. Price, Matthew J. Hoffman, Gunter R. Leguy, Andrew R. Bennett, Sarah L. Bradley, Katherine J. Evans, Jeremy G. Fyke, Joseph H. Kennedy, Mauro Perego, Douglas M. Ranken, William J. Sacks (+3 others)
2019 Geoscientific Model Development  
H.  ...  Thickness-based calving is applied not to CF cells with H < H min c but rather to cells with H eff < H min c .  ... 
doi:10.5194/gmd-12-387-2019 fatcat:jrij6tdhhfdw3i2clusnac3psu

Description and Evaluation of the Community Ice Sheet Model (CISM) v2.1

William H. Lipscomb, Stephen F. Price, Matthew J. Hoffman, Gunter R. Leguy, Andrew R. Bennett, Sarah L. Bradley, Katherine J. Evans, Jeremy G. Fyke, Joseph H. Kennedy, Mauro Perego, Douglas M. Ranken, William J. Sacks (+3 others)
2018 Geoscientific Model Development Discussions  
Thickness-based calving is applied not to CF cells with H < H min c , but rather to cells with H eff < H min c .  ...  The x component of (25) can be rearranged and divided by H: 15 βu b H = 1 H ∂ ∂x 2Hη 2 ∂ū ∂x + ∂v ∂y + 1 H ∂ ∂y Hη ∂ū ∂y + ∂v ∂x − ρ i g ∂s ∂x . (26) From (23), the RHS of (26) is just −(ηu z ) z , giving  ... 
doi:10.5194/gmd-2018-151 fatcat:54o6xlcxqfeybdgblsd27nrkzu

The Community Climate System Model Version 4

Peter R. Gent, Gokhan Danabasoglu, Leo J. Donner, Marika M. Holland, Elizabeth C. Hunke, Steve R. Jayne, David M. Lawrence, Richard B. Neale, Philip J. Rasch, Mariana Vertenstein, Patrick H. Worley, Zong-Liang Yang (+1 others)
2011 Journal of Climate  
The fourth version of the Community Climate System Model (CCSM4) was recently completed and released to the climate community. This paper describes developments to all CCSM components, and documents fully coupled preindustrial control runs compared to the previous version, CCSM3. Using the standard atmosphere and land resolution of 18 results in the sea surface temperature biases in the major upwelling regions being comparable to the 1.48-resolution CCSM3. Two changes to the deep convection
more » ... me in the atmosphere component result in CCSM4 producing El Niñ o-Southern Oscillation variability with a much more realistic frequency distribution than in CCSM3, although the amplitude is too large compared to observations. These changes also improve the Madden-Julian oscillation and the frequency distribution of tropical precipitation. A new overflow parameterization in the ocean component leads to an improved simulation of the Gulf Stream path and the North Atlantic Ocean meridional overturning circulation. Changes to the CCSM4 land component lead to a much improved annual cycle of water storage, especially in the tropics. The CCSM4 sea ice component uses much more realistic albedos than CCSM3, and for several reasons the Arctic sea ice concentration is improved in CCSM4. An ensemble of twentieth-century simulations produces a good match to the observed September Arctic sea ice extent from 1979 to 2005. The CCSM4 ensemble mean increase in globally averaged surface temperature between 1850 and 2005 is larger than the observed increase by about 0.48C. This is consistent with the fact that CCSM4 does not include a representation of the indirect effects of aerosols, although other factors may come into play. The CCSM4 still has significant biases, such as the mean precipitation distribution in the tropical Pacific Ocean, too much low cloud in the Arctic, and the latitudinal distributions of shortwave and longwave cloud forcings.
doi:10.1175/2011jcli4083.1 fatcat:yrii4jlaujerjpehi6xdkbuvra

PORTING AND PERFORMANCE OF THE COMMUNITY CLIMATE SYSTEM MODEL (CCSM3) ON THE CRAY X1

George R Carr, Ilene L Carpenter, Matthew J Cordery, John B Drake, Michael W Ham, Forrest M Hoffman, Patrick H Worley
2005 Use of High Performance Computing in Meteorology  
Control of this is a runtime option [Worley, 2005] . Another feature of CAM and CLM is the ability to specify a work unit that controls the array length of some of the primary work units.  ... 
doi:10.1142/9789812701831_0018 fatcat:arwn4np4grabxjb4uwhzm7aavm

Computational performance of ultra-high-resolution capability in the Community Earth System Model

John M. Dennis, Mariana Vertenstein, Patrick H. Worley, Arthur A. Mirin, Anthony P. Craig, Robert Jacob, Sheri Mickelson
2012 The international journal of high performance computing applications  
Patrick H. Worley is a senior research computer scientist in the Computer Science and Mathematics Division of Oak Ridge National Laboratory.  ...  H.  ... 
doi:10.1177/1094342012436965 fatcat:m6xq2g6rs5hepe2jck3rp37rle

A prototype two-decade fully-coupled fine-resolution CCSM simulation

Julie L. McClean, David C. Bader, Frank O. Bryan, Mathew E. Maltrud, John M. Dennis, Arthur A. Mirin, Philip W. Jones, Yoo Yin Kim, Detelina P. Ivanova, Mariana Vertenstein, James S. Boyle, Robert L. Jacob (+3 others)
2011 Ocean Modelling  
The cross-track extent was identified by 178 differencing SST before the storm and 24 hours afterwards; h was calculated using a 0. , is a major scientific challenge.  ...  the upper water column to pre-storm 173 temperatures can be approximated by: 174 € Q = ρ 0 ∫∫∫ C P ΔTdhdWdL = 5.8 ×10 20 J 175 where ΔT is the magnitude of the negative part of the temperature anomaly, h  ... 
doi:10.1016/j.ocemod.2011.02.011 fatcat:xsbqyqptfbfnbnihfoizvfs6da

Complications, Mortality, and Functional Decline in Patients 80 Years or Older Undergoing Major Head and Neck Ablation and Reconstruction

Tanya Fancy, Andrew T. Huang, Jason I. Kass, Eric D. Lamarre, Patrick Tassone, Avinash V. Mantravadi, Mohamedkazim M. Alwani, Rahul S. Subbarayan, Andrés M. Bur, Mitchell L. Worley, Evan M. Graboyes, Caitlin P. McMullen (+16 others)
2019 JAMA Otolaryngology - Head and Neck Surgery  
. (%) c No 214 (76.2) 1 [Reference] 1 [Reference] 1 [Reference] Yes 67 (23.8) 0.91 (0.49-1.67) 0.99 (0.42-2.35) 1.47 (0.63-3.43) Duration of surgery, median (range), h 8.7 (1.5-20.8) 1.10  ...  Maxilla, oral cavity, or oropharynx 168 (59.8) 39 (41.1) 19.0 (7.6 to 30.4) Larynx, hypopharynx, or esophagus 22 (7.8) 16 (16.8) −9.0 (−17.2 to −0.8) Duration of surgery, median (range), h  ... 
doi:10.1001/jamaoto.2019.2768 pmid:31600390 pmcid:PMC6802247 fatcat:vl5mbywssfesngphyefs34eroe
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