Julien Langou

88 papers A* 1A 7B 3C 1Misc 4Journal 57Unranked 13
YearRankTypeTitle / Venue / Authors
2025 J jnl
2024 NSF CSSI-Cybertraining-SCIPE PI Meeting August 12 to 13, 2024, Charlotte, NC.
CoRR
Abani K. Patra, Mary P. Thomas, Elias Bou-Harb, Jeffrey C. Carver, Yuebin Guo, Ratnesh Kumar, Julien Langou, Guoyu Lu, Vivak Patel, Marianna Safronova, Isla Simpson, Dhruva Chakravorty, Jane Combs, Hantao Cui, Sushil K. Prasad, Adnan Rajib, Susan Rathbun, Erik Saule, Alan Sussman, Shaowen Wang, Sarina Zhe Zhang, Ben Brown, Varun Chandola, Daniel Crawford, Ian T. Foster, Dave Hart, Mike Heroux, Mary Ann Leung, Benjamin Lynch, Dan Negrut, D. K. Panda, Manish Parashar, Melissa Kline Struhl, George K. Thiruvathukal
2024 J jnl
A new deflation criterion for the QZ algorithm.
Numer. Linear Algebra Appl.
Thijs Steel, Raf Vandebril, Julien Langou
2024 J jnl
Communication efficient application of sequences of planar rotations to a matrix.
CoRR
Thijs Steel, Julien Langou
2024 J jnl
Probabilistic Analysis of Least Squares, Orthogonal Projection, and QR Factorization Algorithms Subject to Gaussian Noise.
CoRR
Ali Lotfi, Julien Langou, Mohammad Meysami
2024 B conf
Tightening I/O Lower Bounds through the Hourglass Dependency Pattern.
SPAA
Lionel Eyraud-Dubois, Guillaume Iooss, Julien Langou, Fabrice Rastello
2024 J jnl
Tightening I/O Lower Bounds through the Hourglass Dependency Pattern.
CoRR
Lionel Eyraud-Dubois, Guillaume Iooss, Julien Langou, Fabrice Rastello
2022 J jnl
A new deflation criterion for the QZ algorithm.
CoRR
Thijs Steel, Raf Vandebril, Julien Langou
2022 B conf
I/O-Optimal Algorithms for Symmetric Linear Algebra Kernels.
SPAA
Olivier Beaumont, Lionel Eyraud-Dubois, Julien Langou, Mathieu Vérité
2022 J jnl
I/O-Optimal Algorithms for Symmetric Linear Algebra Kernels.
CoRR
Olivier Beaumont, Lionel Eyraud-Dubois, Mathieu Vérité, Julien Langou
2022 J jnl
Low-synch Gram-Schmidt with delayed reorthogonalization for Krylov solvers.
Parallel Comput.
Daniel Bielich, Julien Langou, Stephen J. Thomas, Kasia Swirydowicz, Ichitaro Yamazaki, Erik G. Boman
2022 J jnl
Numerical analysis of Givens rotation.
CoRR
Weslley da Silva Pereira, Ali Lotfi, Julien Langou
2022 — conf
Proposed Consistent Exception Handling for the BLAS and LAPACK.
Correctness@SC
James Demmel, Jack J. Dongarra, Mark Gates, Greg Henry, Julien Langou, Xiaoye S. Li, Piotr Luszczek, Weslley S. Pereira, E. Jason Riedy, Cindy Rubio-González
2022 J jnl
Proposed Consistent Exception Handling for the BLAS and LAPACK.
CoRR
James Demmel, Jack J. Dongarra, Mark Gates, Greg Henry, Julien Langou, Xiaoye S. Li, Piotr Luszczek, Weslley da Silva Pereira, E. Jason Riedy, Cindy Rubio-González
2022 A conf
Symmetric Block-Cyclic Distribution: Fewer Communications Leads to Faster Dense Cholesky Factorization.
SC
Olivier Beaumont, Philippe Duchon, Lionel Eyraud-Dubois, Julien Langou, Mathieu Vérité
2021 J jnl
Low synchronization Gram-Schmidt and generalized minimal residual algorithms.
Numer. Linear Algebra Appl.
Katarzyna Swirydowicz, Julien Langou, Shreyas Ananthan, Ulrike Meier Yang, Stephen J. Thomas
2021 J jnl
Low-Synch Gram-Schmidt with Delayed Reorthogonalization for Krylov Solvers.
CoRR
Daniel Bielich, Julien Langou, Stephen J. Thomas, Kasia Swirydowicz, Ichitaro Yamazaki, Erik G. Boman
2020 — conf
A Comparison of Several Fault-Tolerance Methods for the Detection and Correction of Floating-Point Errors in Matrix-Matrix Multiplication.
Euro-Par Workshops
Valentin Le Fèvre, Thomas Hérault, Julien Langou, Yves Robert
2020 — conf
A Makespan Lower Bound for the Tiled Cholesky Factorization Based on ALAP Schedule.
Euro-Par
Olivier Beaumont, Julien Langou, Willy Quach, Alena Shilova
2020 A* conf
Automated derivation of parametric data movement lower bounds for affine programs.
PLDI
Auguste Olivry, Julien Langou, Louis-Noël Pouchet, P. Sadayappan, Fabrice Rastello
2019 J jnl
Automated Derivation of Parametric Data Movement Lower Bounds for Affine Programs.
CoRR
Auguste Olivry, Julien Langou, Louis-Noël Pouchet, P. Sadayappan, Fabrice Rastello
2018 J jnl
Low synchronization GMRES algorithms.
CoRR
Kasia Swirydowicz, Julien Langou, Shreyas Ananthan, Ulrike Meier Yang, Stephen J. Thomas
2017 A conf
Bidiagonalization and R-Bidiagonalization: Parallel Tiled Algorithms, Critical Paths and Distributed-Memory Implementation.
IPDPS
Mathieu Faverge, Julien Langou, Yves Robert, Jack J. Dongarra
2017 Misc conf
Fast Parallel Randomized QR with Column Pivoting Algorithms for Reliable Low-Rank Matrix Approximations.
HiPC
Jianwei Xiao, Ming Gu, Julien Langou
2016 J jnl
A backward/forward recovery approach for the preconditioned conjugate gradient method.
J. Comput. Sci.
Massimiliano Fasi, Julien Langou, Yves Robert, Bora Uçar
2016 J jnl
Bidiagonalization with Parallel Tiled Algorithms.
CoRR
Mathieu Faverge, Julien Langou, Yves Robert, Jack J. Dongarra
2015 J jnl
A Backward/Forward Recovery Approach for the Preconditioned Conjugate Gradient Method.
CoRR
Massimiliano Fasi, Julien Langou, Yves Robert, Bora Uçar
2015 J jnl
A Makespan Lower Bound for the Scheduling of the Tiled Cholesky Factorization based on ALAP scheduling.
CoRR
Willy Quach, Julien Langou
2015 J jnl
Mixing LU and QR factorization algorithms to design high-performance dense linear algebra solvers.
J. Parallel Distributed Comput.
Mathieu Faverge, Julien Herrmann, Julien Langou, Bradley R. Lowery, Yves Robert, Jack J. Dongarra
2014 A conf
Designing LU-QR Hybrid Solvers for Performance and Stability.
IPDPS
Mathieu Faverge, Julien Herrmann, Julien Langou, Bradley R. Lowery, Yves Robert, Jack J. Dongarra
2014 J jnl
Designing LU-QR hybrid solvers for performance and stability.
CoRR
Mathieu Faverge, Julien Herrmann, Julien Langou, Bradley R. Lowery, Yves Robert, Jack J. Dongarra
2013 J jnl
A Greedy Algorithm for Optimally Pipelining a Reduction.
CoRR
Bradley R. Lowery, Julien Langou
2013 J jnl
Hierarchical QR factorization algorithms for multi-core clusters.
Parallel Comput.
Jack J. Dongarra, Mathieu Faverge, Thomas Hérault, Mathias Jacquelin, Julien Langou, Yves Robert
2013 J jnl
Level-3 Cholesky Factorization Routines Improve Performance of Many Cholesky Algorithms.
ACM Trans. Math. Softw.
Fred G. Gustavson, Jerzy Wasniewski, Jack J. Dongarra, José R. Herrero, Julien Langou
2013 — conf
Topic 10: Parallel Numerical Algorithms - (Introduction).
Euro-Par
Julien Langou, Matthias Bolten, Laura Grigori, Marián Vajtersic
2012 — conf
Abstract: Matrices Over Runtime Systems at Exascale.
SC Companion
Emmanuel Agullo, George Bosilca, Bérenger Bramas, Cedric Castagnede, Olivier Coulaud, Eric Darve, Jack J. Dongarra, Mathieu Faverge, Nathalie Furmento, Luc Giraud, Xavier Lacoste, Julien Langou, Hatem Ltaief, Matthias Messner, Raymond Namyst, Pierre Ramet, Toru Takahashi, Samuel Thibault, Stanimire Tomov, Ichitaro Yamazaki
2012 J jnl
Communication-optimal Parallel and Sequential QR and LU Factorizations.
SIAM J. Sci. Comput.
James Demmel, Laura Grigori, Mark Hoemmen, Julien Langou
2012 J jnl
Flexible Variants of Block Restarted GMRES Methods with Application to Geophysics.
SIAM J. Sci. Comput.
Henri Calandra, Serge Gratton, Julien Langou, Xavier Pinel, Xavier Vasseur
2012 A conf
Hierarchical QR Factorization Algorithms for Multi-core Cluster Systems.
IPDPS
Jack J. Dongarra, Mathieu Faverge, Thomas Hérault, Julien Langou, Yves Robert
2012 — conf
Poster: Matrices over Runtime Systems at Exascale.
SC Companion
Emmanuel Agullo, George Bosilca, Bérenger Bramas, Cedric Castagnede, Olivier Coulaud, Eric Darve, Jack J. Dongarra, Mathieu Faverge, Nathalie Furmento, Luc Giraud, Xavier Lacoste, Julien Langou, Hatem Ltaief, Matthias Messner, Raymond Namyst, Pierre Ramet, Toru Takahashi, Samuel Thibault, Stanimire Tomov, Ichitaro Yamazaki
2011 J jnl
Any admissible cycle-convergence behavior is possible for restarted GMRES at its initial cycles.
Numer. Linear Algebra Appl.
Eugene Vecharynski, Julien Langou
2011 — conf
Flexible Development of Dense Linear Algebra Algorithms on Massively Parallel Architectures with DPLASMA.
IPDPS Workshops
George Bosilca, Aurélien Bouteiller, Anthony Danalis, Mathieu Faverge, Azzam Haidar, Thomas Hérault, Jakub Kurzak, Julien Langou, Pierre Lemarinier, Hatem Ltaief, Piotr Luszczek, Asim YarKhan, Jack J. Dongarra
2011 J jnl
Hierarchical QR factorization algorithms for multi-core cluster systems
CoRR
Jack J. Dongarra, Mathieu Faverge, Thomas Hérault, Julien Langou, Yves Robert
2011 C conf
LU factorization for accelerator-based systems.
AICCSA
Emmanuel Agullo, Cédric Augonnet, Jack J. Dongarra, Mathieu Faverge, Julien Langou, Hatem Ltaief, Stanimire Tomov
2011 J jnl
QCG-OMPI: MPI applications on grids.
Future Gener. Comput. Syst.
Emmanuel Agullo, Camille Coti, Thomas Hérault, Julien Langou, Sylvain Peyronnet, Ala Rezmerita, Franck Cappello, Jack J. Dongarra
2011 J jnl
Tiled QR factorization algorithms
CoRR
Henricus Bouwmeester, Mathias Jacquelin, Julien Langou, Yves Robert
2011 A conf
Tiled QR factorization algorithms.
SC
Henricus Bouwmeester, Mathias Jacquelin, Julien Langou, Yves Robert
2010 J jnl
A Critical Path Approach to Analyzing Parallelism of Algorithmic Variants. Application to Cholesky Inversion
CoRR
Henricus Bouwmeester, Julien Langou
2010 A conf
QR factorization of tall and skinny matrices in a grid computing environment.
IPDPS
Emmanuel Agullo, Camille Coti, Jack J. Dongarra, Thomas Hérault, Julien Langou
2010 J jnl
Rectangular full packed format for cholesky's algorithm: factorization, solution, and inversion.
ACM Trans. Math. Softw.
Fred G. Gustavson, Jerzy Wasniewski, Jack J. Dongarra, Julien Langou
2010 J jnl
The Cycle-Convergence of Restarted GMRES for Normal Matrices Is Sublinear.
SIAM J. Sci. Comput.
Eugene Vecharynski, Julien Langou
2010 J jnl
Towards an Efficient Tile Matrix Inversion of Symmetric Positive Definite Matrices on Multicore Architectures
CoRR
Emmanuel Agullo, Henricus Bouwmeester, Jack J. Dongarra, Jakub Kurzak, Julien Langou, Lee Rosenberg
2010 — conf
Towards an Efficient Tile Matrix Inversion of Symmetric Positive Definite Matrices on Multicore Architectures.
VECPAR
Emmanuel Agullo, Henricus Bouwmeester, Jack J. Dongarra, Jakub Kurzak, Julien Langou, Lee Rosenberg
2009 J jnl
A class of parallel tiled linear algebra algorithms for multicore architectures.
Parallel Comput.
Alfredo Buttari, Julien Langou, Jakub Kurzak, Jack J. Dongarra
2009 J jnl
Accelerating scientific computations with mixed precision algorithms.
Comput. Phys. Commun.
Marc Baboulin, Alfredo Buttari, Jack J. Dongarra, Jakub Kurzak, Julie Langou, Julien Langou, Piotr Luszczek, Stanimire Tomov
2009 J jnl
Algorithm-based fault tolerance applied to high performance computing.
J. Parallel Distributed Comput.
George Bosilca, Remi Delmas, Jack J. Dongarra, Julien Langou
2009 J jnl
Computing the conditioning of the components of a linear least-squares solution.
Numer. Linear Algebra Appl.
Marc Baboulin, Jack J. Dongarra, Serge Gratton, Julien Langou
2009 J jnl
QR Factorization of Tall and Skinny Matrices in a Grid Computing Environment
CoRR
Emmanuel Agullo, Camille Coti, Jack J. Dongarra, Thomas Hérault, Julien Langou
2009 J jnl
Rectangular Full Packed Format for Cholesky's Algorithm: Factorization, Solution and Inversion
CoRR
Fred G. Gustavson, Jerzy Wasniewski, Jack J. Dongarra, Julien Langou
2009 J jnl
The Problem With the Linpack Benchmark 1.0 Matrix Generator.
Int. J. High Perform. Comput. Appl.
Jack J. Dongarra, Julien Langou
2008 J jnl
Accelerating Scientific Computations with Mixed Precision Algorithms
CoRR
Marc Baboulin, Alfredo Buttari, Jack J. Dongarra, Jakub Kurzak, Julie Langou, Julien Langou, Piotr Luszczek, Stanimire Tomov
2008 J jnl
Algorithmic Based Fault Tolerance Applied to High Performance Computing
CoRR
George Bosilca, Remi Delmas, Jack J. Dongarra, Julien Langou
2008 J jnl
Communication-avoiding parallel and sequential QR factorizations
CoRR
James Demmel, Laura Grigori, Mark Hoemmen, Julien Langou
2008 J jnl
Parallel tiled QR factorization for multicore architectures.
Concurr. Comput. Pract. Exp.
Alfredo Buttari, Julien Langou, Jakub Kurzak, Jack J. Dongarra
2007 J jnl
A Class of Parallel Tiled Linear Algebra Algorithms for Multicore Architectures
CoRR
Alfredo Buttari, Julien Langou, Jakub Kurzak, Jack J. Dongarra
2007 J jnl
A distributed packed storage for large dense parallel in-core calculations.
Concurr. Comput. Pract. Exp.
Marc Baboulin, Luc Giraud, Serge Gratton, Julien Langou
2007 — conf
Advanced MPI Programming.
PVM/MPI
Julien Langou, George Bosilca
2007 J jnl
Convergence in Backward Error of Relaxed GMRES.
SIAM J. Sci. Comput.
Luc Giraud, Serge Gratton, Julien Langou
2007 J jnl
Mixed Precision Iterative Refinement Techniques for the Solution of Dense Linear Systems.
Int. J. High Perform. Comput. Appl.
Alfredo Buttari, Jack J. Dongarra, Julie Langou, Julien Langou, Piotr Luszczek, Jakub Kurzak
2007 Misc conf
Parallel Tiled QR Factorization for Multicore Architectures.
PPAM
Alfredo Buttari, Julien Langou, Jakub Kurzak, Jack J. Dongarra
2007 J jnl
Performance Optimization and Modeling of Blocked Sparse Kernels.
Int. J. High Perform. Comput. Appl.
Alfredo Buttari, Victor Eijkhout, Julien Langou, Salvatore Filippone
2007 — ch.
Prospectus for a Dense Linear Algebra Software Library.
Handbook of Parallel Computing
Yozo Hida, James Demmel, Julien Langou, Jakub Kurzak, Ming Gu, Alfredo Buttari, Stanimire Tomov, Piotr Luszczek, Julie Langou, Osni Marques, Christof Vömel, Xiaoye S. Li, E. Jason Riedy, Jack J. Dongarra, William Kahan, Beresford N. Parlett, David Bindel
2007 J jnl
Recovery Patterns for Iterative Methods in a Parallel Unstable Environment.
SIAM J. Sci. Comput.
Julien Langou, Zizhong Chen, George Bosilca, Jack J. Dongarra
2006 J jnl
A note on the error analysis of classical Gram-Schmidt.
Numerische Mathematik
Alicja Smoktunowicz, Jesse L. Barlow, Julien Langou
2006 J jnl
Conjugate-gradient eigenvalue solvers in computing electronic properties of nanostructure architectures.
Int. J. Comput. Sci. Eng.
Stanimire Tomov, Julien Langou, Jack J. Dongarra, Andrew Canning, Lin-Wang Wang
2006 Misc conf
Exploiting Mixed Precision Floating Point Hardware in Scientific Computations.
High Performance Computing Workshop
Alfredo Buttari, Jack J. Dongarra, Jakub Kurzak, Julie Langou, Julien Langou, Piotr Luszczek, Stanimire Tomov
2006 — ch.
Parallel Linear Algebra Software.
Parallel Processing for Scientific Computing
Victor Eijkhout, Julien Langou, Jack J. Dongarra
2006 — conf
Prospectus for the Next LAPACK and ScaLAPACK Libraries.
PARA
James Demmel, Jack J. Dongarra, Beresford N. Parlett, William Kahan, Ming Gu, David Bindel, Yozo Hida, Xiaoye S. Li, Osni Marques, E. Jason Riedy, Christof Vömel, Julien Langou, Piotr Luszczek, Jakub Kurzak, Alfredo Buttari, Julie Langou, Stanimire Tomov
2006 — conf
Recent Advances in Dense Linear Algebra: Minisymposium Abstract.
PARA
Daniel Kressner, Julien Langou
2006 J jnl
Self-adapting numerical software (SANS) effort.
IBM J. Res. Dev.
Jack J. Dongarra, George Bosilca, Zizhong Chen, Victor Eijkhout, Graham E. Fagg, Erika Fuentes, Julien Langou, Piotr Luszczek, Jelena Pjesivac-Grbovic, Keith Seymour, Haihang You, Sathish S. Vadhiyar
2006 — conf
The Impact of Multicore on Math Software.
PARA
Alfredo Buttari, Jack J. Dongarra, Jakub Kurzak, Julien Langou, Piotr Luszczek, Stanimire Tomov
2006 A conf
Tools and techniques for performance - Exploiting the performance of 32 bit floating point arithmetic in obtaining 64 bit accuracy (revisiting iterative refinement for linear systems).
SC
Julie Langou, Julien Langou, Piotr Luszczek, Jakub Kurzak, Alfredo Buttari, Jack J. Dongarra
2005 J jnl
Algorithm 842: A set of GMRES routines for real and complex arithmetics on high performance computers.
ACM Trans. Math. Softw.
Valérie Frayssé, Luc Giraud, Serge Gratton, Julien Langou
2005 Misc conf
Comparison of Nonlinear Conjugate-Gradient Methods for Computing the Electronic Properties of Nanostructure Architectures.
International Conference on Computational Science (3)
Stanimire Tomov, Julien Langou, Andrew Canning, Lin-Wang Wang, Jack J. Dongarra
2005 B conf
Fault tolerant high performance computing by a coding approach.
PPoPP
Zizhong Chen, Graham E. Fagg, Edgar Gabriel, Julien Langou, Thara Angskun, George Bosilca, Jack J. Dongarra
2005 — conf
Hash Functions for Datatype Signatures in MPI.
PVM/MPI
Julien Langou, George Bosilca, Graham E. Fagg, Jack J. Dongarra
2005 J jnl
Rounding error analysis of the classical Gram-Schmidt orthogonalization process.
Numerische Mathematik
Luc Giraud, Julien Langou, Miroslav Rozlozník, Jasper van den Eshof
2004 J jnl
A Rank-
SIAM J. Matrix Anal. Appl.
Luc Giraud, Serge Gratton, Julien Langou
2003 J jnl
A Robust Criterion for the Modified Gram-Schmidt Algorithm with Selective Reorthogonalization.
SIAM J. Sci. Comput.
Luc Giraud, Julien Langou