J. Alimi, V. Bouillot, Y. Rasera, V. Reverdy, Pier Stefano Corasaniti, Irène Balmès, S. Requena, Xavier Delaruelle, Jean-Noel Richet
{"title":"First-ever full observable universe simulation","authors":"J. Alimi, V. Bouillot, Y. Rasera, V. Reverdy, Pier Stefano Corasaniti, Irène Balmès, S. Requena, Xavier Delaruelle, Jean-Noel Richet","doi":"10.1109/SC.2012.58","DOIUrl":"https://doi.org/10.1109/SC.2012.58","url":null,"abstract":"We have performed the first-ever numerical N-body simulation of the full observable universe (DEUS \"Dark Energy Universe Simulation\" FUR \"Full Universe Run\"). This has evolved 550 billion particles on an Adaptive Mesh Refinement grid with more than two trillion computing points along the entire evolutionary history of the universe and across 6 order of magnitudes length scales, from the size of the Milky Way to that of the whole observable Universe. To date, this is the largest and most advanced cosmological simulation ever run. It provides unique information on the formation and evolution of the largest structure in the universe and an exceptional support to future observational programs dedicated to mapping the distribution of matter and galaxies in the universe. The simulation has run on 4752 (of 5040) thin nodes of BULL supercomputer CURIE, using more than 300 TB of memory for 10 million hours of computing time. About 50 PBytes of data were generated throughout the run. Using an advanced and innovative reduction workflow the amount of useful stored data has been reduced to 500 TBytes.","PeriodicalId":217221,"journal":{"name":"2012 International Conference for High Performance Computing, Networking, Storage and Analysis","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121988797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Automatic generation of software pipelines for heterogeneous parallel systems","authors":"J. Pienaar, S. Chakradhar, A. Raghunathan","doi":"10.1109/SC.2012.22","DOIUrl":"https://doi.org/10.1109/SC.2012.22","url":null,"abstract":"Pipelining is a well-known approach to increasing parallelism and performance. We address the problem of software pipelining for heterogeneous parallel platforms that consist of different multi-core and many-core processing units. In this context, pipelining involves two key steps -- partitioning an application into stages and mapping and scheduling the stages onto the processing units of the heterogeneous platform. We show that the inter-dependency between these steps is a critical challenge that must be addressed in order to achieve high performance. We propose an Automatic Heterogeneous Pipelining framework (AHP) that generates an optimized pipelined implementation of a program from an annotated unpipelined specification. Across three complex applications (image classification, object detection, and document retrieval) and two heterogeneous platforms (Intel Xeon multi-core CPUs with Intel MIC and NVIDIA GPGPU accelerators), AHP achieves a throughput improvement of up to 1.53x (1.37x on average) over a heterogeneous baseline that exploits data and task parallelism.","PeriodicalId":217221,"journal":{"name":"2012 International Conference for High Performance Computing, Networking, Storage and Analysis","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126223798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Henschel, Stephen C. Simms, David Y. Hancock, Scott Michael, Tom Johnson, Nathan Heald, T. William, Donald K. Berry, Matthew Allen, R. Knepper, M. Davy, Matthew R. Link, C. Stewart
{"title":"Demonstrating Lustre over a 100Gbps wide area network of 3,500km","authors":"R. Henschel, Stephen C. Simms, David Y. Hancock, Scott Michael, Tom Johnson, Nathan Heald, T. William, Donald K. Berry, Matthew Allen, R. Knepper, M. Davy, Matthew R. Link, C. Stewart","doi":"10.1109/SC.2012.43","DOIUrl":"https://doi.org/10.1109/SC.2012.43","url":null,"abstract":"As part of the SCinet Research Sandbox at the Supercomputing 2011 conference, Indiana University (IU) demonstrated use of the Lustre high performance parallel file system over a dedicated 100 Gbps wide area network (WAN) spanning more than 3,500 km (2,175 mi). This demonstration functioned as a proof of concept and provided an opportunity to study Lustre's performance over a 100 Gbps WAN. To characterize the performance of the network and file system, low level iperf network tests, file system tests with the IOR benchmark, and a suite of real-world applications reading and writing to the file system were run over a latency of 50.5 ms. In this article we describe the configuration and constraints of the demonstration and outline key findings.","PeriodicalId":217221,"journal":{"name":"2012 International Conference for High Performance Computing, Networking, Storage and Analysis","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126866742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Compiler-directed file layout optimization for hierarchical storage systems","authors":"W. Ding, Yuanrui Zhang, M. Kandemir, S. Son","doi":"10.3233/SPR-130365","DOIUrl":"https://doi.org/10.3233/SPR-130365","url":null,"abstract":"File layout of array data is a critical factor that effects the behavior of storage caches, and has so far taken not much attention in the context of hierarchical storage systems. The main contribution of this paper is a compiler-driven file layout optimization scheme for hierarchical storage caches. This approach, fully automated within an optimizing compiler, analyzes a multi-threaded application code and determines a file layout for each disk-resident array referenced by the code, such that the performance of the target storage cache hierarchy is maximized. We tested our approach using 16 I/O intensive application programs and compared its performance against two previously proposed approaches under different cache space management schemes. Our experimental results show that the proposed approach improves the execution time of these parallel applications by 23.7% on average.","PeriodicalId":217221,"journal":{"name":"2012 International Conference for High Performance Computing, Networking, Storage and Analysis","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126287093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"On distributed file tree walk of parallel file systems","authors":"Jharrod Lafon, S. Misra, John R. Bringhurst","doi":"10.1109/SC.2012.82","DOIUrl":"https://doi.org/10.1109/SC.2012.82","url":null,"abstract":"Supercomputers generate vast amounts of data, typically organized into large directory hierarchies on parallel file systems. While the supercomputing applications are parallel, the tools used to process them requiring complete directory traversais, are typically serial. We present an algorithm framework and three fully distributed algorithms for traversing large parallel file systems, and performing file operations in parallel. The first algorithm introduces a randomized work-stealing scheduler; the second improves the first with proximity-awareness; and the third improves upon the second by using a hybrid approach. We have tested our implementation on Cielo, a 1.37 petaflop supercomputer at the Los Alamos National Laboratory and its 7 petabyte file system. Test results show that our algorithms execute orders of magnitude faster than state-of-the-art algorithms while achieving ideal load balancing and low communication cost. We present performance insights from the use of our algorithms in production systems at LANL, performing daily file system operations.","PeriodicalId":217221,"journal":{"name":"2012 International Conference for High Performance Computing, Networking, Storage and Analysis","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130075920","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"NUMA-aware graph mining techniques for performance and energy efficiency","authors":"Michael R. Frasca, Kamesh Madduri, P. Raghavan","doi":"10.5555/2388996.2389125","DOIUrl":"https://doi.org/10.5555/2388996.2389125","url":null,"abstract":"We investigate dynamic methods to improve the power and performance profiles of large irregular applications on modern multi-core systems. In this context, we study a large sparse graph application, Betweenness Centrality, and focus on memory behavior as core count scales. We introduce new techniques to efficiently map the computational demands onto non-uniform memory architectures (NUMA). Our dynamic design adapts to hardware topology and dramatically improves both energy and performance. These gains are more significant at higher core counts. We implement a scheme for adaptive data layout, which reorganizes the graph after observing parallel access patterns, and a dynamic task scheduler that encourages shared data between neighboring cores. We measure performance and energy consumption on a modern multi-core machine and observe that mean execution time is reduced by 51.2% and energy is reduced by 52.4%.","PeriodicalId":217221,"journal":{"name":"2012 International Conference for High Performance Computing, Networking, Storage and Analysis","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129302286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Baker, G. Davidson, T. Evans, S. Hamilton, J. Jarrell, W. Joubert
{"title":"High performance radiation transport simulations: Preparing for TITAN","authors":"C. Baker, G. Davidson, T. Evans, S. Hamilton, J. Jarrell, W. Joubert","doi":"10.1109/SC.2012.64","DOIUrl":"https://doi.org/10.1109/SC.2012.64","url":null,"abstract":"In this paper we describe the Denovo code system. Denovo solves the six-dimensional, steady-state, linear Boltzmann transport equation, of central importance to nuclear technology applications such as reactor core analysis (neutronics), radiation shielding, nuclear forensics and radiation detection. The code features multiple spatial differencing schemes, state-of-the-art linear solvers, the Koch-Baker-Alcouffe (KBA) parallel-wavefront sweep algorithm for inverting the transport operator, a new multilevel energy decomposition method scaling to hundreds of thousands of processing cores, and a modern, novel code architecture that supports straightforward integration of new features. In this paper we discuss the performance of Denovo on the 20+ petaflop ORNL GPU-based system, Titan. We describe algorithms and techniques used to exploit the capabilities of Titan's heterogeneous compute node architecture and the challenges of obtaining good parallel performance for this sparse hyperbolic PDE solver containing inherently sequential computations. Numerical results demonstrating Denovo performance on early Titan hardware are presented.","PeriodicalId":217221,"journal":{"name":"2012 International Conference for High Performance Computing, Networking, Storage and Analysis","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122182482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Critical lock analysis: Diagnosing critical section bottlenecks in multithreaded applications","authors":"Guancheng Chen, P. Stenström","doi":"10.1109/SC.2012.40","DOIUrl":"https://doi.org/10.1109/SC.2012.40","url":null,"abstract":"Critical sections are well known potential performance bottlenecks in multithreaded applications and identifying the ones that inhibit scalability are important for performance optimizations. While previous approaches use idle time as a key measure, we show such a measure is not reliable. The reason is that idleness does not necessarily mean the critical section is on the critical path. We introduce critical lock analysis, a new method for diagnosing critical section bottlenecks in multithreaded applications. Our method firstly identifies the critical sections appearing on the critical path, and then quantifies the impact of such critical sections on the overall performance by using quantitative performance metrics. Case studies show that our method can successfully identify critical sections that are most beneficial for improving overall performance as well as quantify their performance impact on the critical path, which results in a more reliable establishment of the inherent critical section bottlenecks than previous approaches.","PeriodicalId":217221,"journal":{"name":"2012 International Conference for High Performance Computing, Networking, Storage and Analysis","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115102241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jongsoo Park, P. T. P. Tang, M. Smelyanskiy, Daehyun Kim, T. Benson
{"title":"Efficient backprojection-based synthetic aperture radar computation with many-core processors","authors":"Jongsoo Park, P. T. P. Tang, M. Smelyanskiy, Daehyun Kim, T. Benson","doi":"10.3233/SPR-130372","DOIUrl":"https://doi.org/10.3233/SPR-130372","url":null,"abstract":"Tackling computationally challenging problems with high efficiency often requires the combination of algorithmic innovation, advanced architecture, and thorough exploitation of parallelism. We demonstrate this synergy through synthetic aperture radar (SAR) via backprojection, an image reconstruction method that can require hundreds of TFLOPS. Computation cost is significantly reduced by our new algorithm of approximate strength reduction; data movement cost is economized by software locality optimizations facilitated by advanced architecture support; parallelism is fully harnessed in various patterns and granularities. We deliver over 35 billion backprojections per second throughput per compute node on an Intel® Xeon® processor E5-2670-based cluster, equipped with Intel® Xeon Phi coprocessors. This corresponds to processing a 3K×3K image within a second using a single node. Our study can be extended to other settings: backprojection is applicable elsewhere including medical imaging, approximate strength reduction is a general code transformation technique, and many-core processors are emerging as a solution to energy-efficient computing.","PeriodicalId":217221,"journal":{"name":"2012 International Conference for High Performance Computing, Networking, Storage and Analysis","volume":"119 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120894129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jiayuan Meng, V. Morozov, V. Vishwanath, Kalyan Kumaran
{"title":"Dataflow-driven GPU performance projection for multi-kernel transformations","authors":"Jiayuan Meng, V. Morozov, V. Vishwanath, Kalyan Kumaran","doi":"10.1109/SC.2012.42","DOIUrl":"https://doi.org/10.1109/SC.2012.42","url":null,"abstract":"Applications often have a sequence of parallel operations to be offloaded to graphics processors; each operation can become an individual GPU kernel. Developers typically explore a variety of transformations for each kernel. Furthermore, it is well known that efficient data management is critical in achieving high GPU performance and that \"fusing\" multiple kernels into one may greatly improve data locality. Doing so, however, requires transformations across multiple, potentially nested, parallel loops; at the same time, the original code semantics and data dependency must be preserved. Since each kernel may have distinct data access patterns, their combined dataflow can be nontrivial. As a result, the complexity of multi-kernel transformations often leads to significant effort with no guarantee of performance benefits. This paper proposes a dataflow-driven analytical framework to project GPU performance for a sequence of parallel operations. Users need only provide CPU code skeletons for a sequence of parallel loops. The framework can then automatically identify opportunities for multi-kernel transformations and data management. It is also able to project the overall performance without implementing GPU code or using physical hardware.","PeriodicalId":217221,"journal":{"name":"2012 International Conference for High Performance Computing, Networking, Storage and Analysis","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128030787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}