Julien Langou

Publication Activity (10 Years)

Years Active: 2003-2024
Publications (10 Years): 22

Top Topics

Top Venues

Numer. Linear Algebra Appl.

Publications

Thijs Steel, Raf Vandebril, Julien Langou
A new deflation criterion for the QZ algorithm. Numer. Linear Algebra Appl. 31 (1) (2024)
Lionel Eyraud-Dubois, Guillaume Iooss, Julien Langou, Fabrice Rastello
Tightening I/O Lower Bounds through the Hourglass Dependency Pattern. CoRR (2024)
Lionel Eyraud-Dubois, Guillaume Iooss, Julien Langou, Fabrice Rastello
Tightening I/O Lower Bounds through the Hourglass Dependency Pattern. SPAA (2024)
Olivier Beaumont, Lionel Eyraud-Dubois, Julien Langou, Mathieu Vérité
I/O-Optimal Algorithms for Symmetric Linear Algebra Kernels. SPAA (2022)
Weslley da Silva Pereira, Ali Lotfi, Julien Langou
Numerical analysis of Givens rotation. CoRR (2022)
Olivier Beaumont, Lionel Eyraud-Dubois, Mathieu Vérité, Julien Langou
I/O-Optimal Algorithms for Symmetric Linear Algebra Kernels. CoRR (2022)
Thijs Steel, Raf Vandebril, Julien Langou
A new deflation criterion for the QZ algorithm. CoRR (2022)
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
Proposed Consistent Exception Handling for the BLAS and LAPACK. CoRR (2022)
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
Proposed Consistent Exception Handling for the BLAS and LAPACK. Correctness@SC (2022)
Daniel Bielich, Julien Langou, Stephen J. Thomas, Kasia Swirydowicz, Ichitaro Yamazaki, Erik G. Boman
Low-synch Gram-Schmidt with delayed reorthogonalization for Krylov solvers. Parallel Comput. 112 (2022)
Olivier Beaumont, Philippe Duchon, Lionel Eyraud-Dubois, Julien Langou, Mathieu Vérité
Symmetric Block-Cyclic Distribution: Fewer Communications Leads to Faster Dense Cholesky Factorization. SC (2022)
Daniel Bielich, Julien Langou, Stephen J. Thomas, Kasia Swirydowicz, Ichitaro Yamazaki, Erik G. Boman
Low-Synch Gram-Schmidt with Delayed Reorthogonalization for Krylov Solvers. CoRR (2021)
Katarzyna Swirydowicz, Julien Langou, Shreyas Ananthan, Ulrike Meier Yang, Stephen J. Thomas
Low synchronization Gram-Schmidt and generalized minimal residual algorithms. Numer. Linear Algebra Appl. 28 (2) (2021)
Auguste Olivry, Julien Langou, Louis-Noël Pouchet, P. Sadayappan, Fabrice Rastello
Automated derivation of parametric data movement lower bounds for affine programs. PLDI (2020)
Valentin Le Fèvre, Thomas Hérault, Julien Langou, Yves Robert
A Comparison of Several Fault-Tolerance Methods for the Detection and Correction of Floating-Point Errors in Matrix-Matrix Multiplication. Euro-Par Workshops (2020)
Olivier Beaumont, Julien Langou, Willy Quach, Alena Shilova
A Makespan Lower Bound for the Tiled Cholesky Factorization Based on ALAP Schedule. Euro-Par (2020)
Auguste Olivry, Julien Langou, Louis-Noël Pouchet, P. Sadayappan, Fabrice Rastello
Automated Derivation of Parametric Data Movement Lower Bounds for Affine Programs. CoRR (2019)
Kasia Swirydowicz, Julien Langou, Shreyas Ananthan, Ulrike Meier Yang, Stephen J. Thomas
Low synchronization GMRES algorithms. CoRR (2018)
Mathieu Faverge, Julien Langou, Yves Robert, Jack J. Dongarra
Bidiagonalization and R-Bidiagonalization: Parallel Tiled Algorithms, Critical Paths and Distributed-Memory Implementation. IPDPS (2017)
Jianwei Xiao, Ming Gu, Julien Langou
Fast Parallel Randomized QR with Column Pivoting Algorithms for Reliable Low-Rank Matrix Approximations. HiPC (2017)
Massimiliano Fasi, Julien Langou, Yves Robert, Bora Uçar
A backward/forward recovery approach for the preconditioned conjugate gradient method. J. Comput. Sci. 17 (2016)
Mathieu Faverge, Julien Langou, Yves Robert, Jack J. Dongarra
Bidiagonalization with Parallel Tiled Algorithms. CoRR (2016)
Massimiliano Fasi, Julien Langou, Yves Robert, Bora Uçar
A Backward/Forward Recovery Approach for the Preconditioned Conjugate Gradient Method. CoRR (2015)
Willy Quach, Julien Langou
A Makespan Lower Bound for the Scheduling of the Tiled Cholesky Factorization based on ALAP scheduling. CoRR (2015)
Mathieu Faverge, Julien Herrmann, Julien Langou, Bradley R. Lowery, Yves Robert, Jack J. Dongarra
Mixing LU and QR factorization algorithms to design high-performance dense linear algebra solvers. J. Parallel Distributed Comput. 85 (2015)
Mathieu Faverge, Julien Herrmann, Julien Langou, Bradley R. Lowery, Yves Robert, Jack J. Dongarra
Designing LU-QR Hybrid Solvers for Performance and Stability. IPDPS (2014)
Mathieu Faverge, Julien Herrmann, Julien Langou, Bradley R. Lowery, Yves Robert, Jack J. Dongarra
Designing LU-QR hybrid solvers for performance and stability. CoRR (2014)
Fred G. Gustavson, Jerzy Wasniewski, Jack J. Dongarra, José R. Herrero, Julien Langou
Level-3 Cholesky Factorization Routines Improve Performance of Many Cholesky Algorithms. ACM Trans. Math. Softw. 39 (2) (2013)
Bradley R. Lowery, Julien Langou
A Greedy Algorithm for Optimally Pipelining a Reduction. CoRR (2013)
Jack J. Dongarra, Mathieu Faverge, Thomas Hérault, Mathias Jacquelin, Julien Langou, Yves Robert
Hierarchical QR factorization algorithms for multi-core clusters. Parallel Comput. 39 (4-5) (2013)
Julien Langou, Matthias Bolten, Laura Grigori, Marián Vajtersic
Topic 10: Parallel Numerical Algorithms - (Introduction). Euro-Par (2013)
James Demmel, Laura Grigori, Mark Hoemmen, Julien Langou
Communication-optimal Parallel and Sequential QR and LU Factorizations. SIAM J. Sci. Comput. 34 (1) (2012)
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
Abstract: Matrices Over Runtime Systems at Exascale. SC Companion (2012)
Henri Calandra, Serge Gratton, Julien Langou, Xavier Pinel, Xavier Vasseur
Flexible Variants of Block Restarted GMRES Methods with Application to Geophysics. SIAM J. Sci. Comput. 34 (2) (2012)
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
Poster: Matrices over Runtime Systems at Exascale. SC Companion (2012)
Jack J. Dongarra, Mathieu Faverge, Thomas Hérault, Julien Langou, Yves Robert
Hierarchical QR Factorization Algorithms for Multi-core Cluster Systems. IPDPS (2012)
Emmanuel Agullo, Cédric Augonnet, Jack J. Dongarra, Mathieu Faverge, Julien Langou, Hatem Ltaief, Stanimire Tomov
LU factorization for accelerator-based systems. AICCSA (2011)
Jack J. Dongarra, Mathieu Faverge, Thomas Hérault, Julien Langou, Yves Robert
Hierarchical QR factorization algorithms for multi-core cluster systems CoRR (2011)
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
Flexible Development of Dense Linear Algebra Algorithms on Massively Parallel Architectures with DPLASMA. IPDPS Workshops (2011)
Henricus Bouwmeester, Mathias Jacquelin, Julien Langou, Yves Robert
Tiled QR factorization algorithms CoRR (2011)
Eugene Vecharynski, Julien Langou
Any admissible cycle-convergence behavior is possible for restarted GMRES at its initial cycles. Numer. Linear Algebra Appl. 18 (3) (2011)
Henricus Bouwmeester, Mathias Jacquelin, Julien Langou, Yves Robert
Tiled QR factorization algorithms. SC (2011)
Emmanuel Agullo, Camille Coti, Thomas Hérault, Julien Langou, Sylvain Peyronnet, Ala Rezmerita, Franck Cappello, Jack J. Dongarra
QCG-OMPI: MPI applications on grids. Future Gener. Comput. Syst. 27 (4) (2011)
Eugene Vecharynski, Julien Langou
The Cycle-Convergence of Restarted GMRES for Normal Matrices Is Sublinear. SIAM J. Sci. Comput. 32 (1) (2010)
Henricus Bouwmeester, Julien Langou
A Critical Path Approach to Analyzing Parallelism of Algorithmic Variants. Application to Cholesky Inversion CoRR (2010)
Emmanuel Agullo, Henricus Bouwmeester, Jack J. Dongarra, Jakub Kurzak, Julien Langou, Lee Rosenberg
Towards an Efficient Tile Matrix Inversion of Symmetric Positive Definite Matrices on Multicore Architectures CoRR (2010)
Emmanuel Agullo, Camille Coti, Jack J. Dongarra, Thomas Hérault, Julien Langou
QR factorization of tall and skinny matrices in a grid computing environment. IPDPS (2010)
Fred G. Gustavson, Jerzy Wasniewski, Jack J. Dongarra, Julien Langou
Rectangular full packed format for cholesky's algorithm: factorization, solution, and inversion. ACM Trans. Math. Softw. 37 (2) (2010)
Emmanuel Agullo, Henricus Bouwmeester, Jack J. Dongarra, Jakub Kurzak, Julien Langou, Lee Rosenberg
Towards an Efficient Tile Matrix Inversion of Symmetric Positive Definite Matrices on Multicore Architectures. VECPAR (2010)
Emmanuel Agullo, Camille Coti, Jack J. Dongarra, Thomas Hérault, Julien Langou
QR Factorization of Tall and Skinny Matrices in a Grid Computing Environment CoRR (2009)
Jack J. Dongarra, Julien Langou
The Problem With the Linpack Benchmark 1.0 Matrix Generator. Int. J. High Perform. Comput. Appl. 23 (1) (2009)
Marc Baboulin, Alfredo Buttari, Jack J. Dongarra, Jakub Kurzak, Julie Langou, Julien Langou, Piotr Luszczek, Stanimire Tomov
Accelerating scientific computations with mixed precision algorithms. Comput. Phys. Commun. 180 (12) (2009)
Fred G. Gustavson, Jerzy Wasniewski, Jack J. Dongarra, Julien Langou
Rectangular Full Packed Format for Cholesky's Algorithm: Factorization, Solution and Inversion CoRR (2009)
George Bosilca, Remi Delmas, Jack J. Dongarra, Julien Langou
Algorithm-based fault tolerance applied to high performance computing. J. Parallel Distributed Comput. 69 (4) (2009)
Alfredo Buttari, Julien Langou, Jakub Kurzak, Jack J. Dongarra
A class of parallel tiled linear algebra algorithms for multicore architectures. Parallel Comput. 35 (1) (2009)
Marc Baboulin, Jack J. Dongarra, Serge Gratton, Julien Langou
Computing the conditioning of the components of a linear least-squares solution. Numer. Linear Algebra Appl. 16 (7) (2009)
Marc Baboulin, Alfredo Buttari, Jack J. Dongarra, Jakub Kurzak, Julie Langou, Julien Langou, Piotr Luszczek, Stanimire Tomov
Accelerating Scientific Computations with Mixed Precision Algorithms CoRR (2008)
Alfredo Buttari, Julien Langou, Jakub Kurzak, Jack J. Dongarra
Parallel tiled QR factorization for multicore architectures. Concurr. Comput. Pract. Exp. 20 (13) (2008)
James Demmel, Laura Grigori, Mark Hoemmen, Julien Langou
Communication-avoiding parallel and sequential QR factorizations CoRR (2008)
George Bosilca, Remi Delmas, Jack J. Dongarra, Julien Langou
Algorithmic Based Fault Tolerance Applied to High Performance Computing CoRR (2008)
Alfredo Buttari, Julien Langou, Jakub Kurzak, Jack J. Dongarra
Parallel Tiled QR Factorization for Multicore Architectures. PPAM (2007)
Alfredo Buttari, Jack J. Dongarra, Julie Langou, Julien Langou, Piotr Luszczek, Jakub Kurzak
Mixed Precision Iterative Refinement Techniques for the Solution of Dense Linear Systems. Int. J. High Perform. Comput. Appl. 21 (4) (2007)
Alfredo Buttari, Julien Langou, Jakub Kurzak, Jack J. Dongarra
A Class of Parallel Tiled Linear Algebra Algorithms for Multicore Architectures CoRR (2007)
Luc Giraud, Serge Gratton, Julien Langou
Convergence in Backward Error of Relaxed GMRES. SIAM J. Sci. Comput. 29 (2) (2007)
Alfredo Buttari, Victor Eijkhout, Julien Langou, Salvatore Filippone
Performance Optimization and Modeling of Blocked Sparse Kernels. Int. J. High Perform. Comput. Appl. 21 (4) (2007)
Julien Langou, Zizhong Chen, George Bosilca, Jack J. Dongarra
Recovery Patterns for Iterative Methods in a Parallel Unstable Environment. SIAM J. Sci. Comput. 30 (1) (2007)
Julien Langou, George Bosilca
Advanced MPI Programming. PVM/MPI (2007)
Marc Baboulin, Luc Giraud, Serge Gratton, Julien Langou
A distributed packed storage for large dense parallel in-core calculations. Concurr. Comput. Pract. Exp. 19 (4) (2007)
Daniel Kressner, Julien Langou
Recent Advances in Dense Linear Algebra: Minisymposium Abstract. PARA (2006)
Julie Langou, Julien Langou, Piotr Luszczek, Jakub Kurzak, Alfredo Buttari, Jack J. Dongarra
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 (2006)
Stanimire Tomov, Julien Langou, Jack J. Dongarra, Andrew Canning, Lin-Wang Wang
Conjugate-gradient eigenvalue solvers in computing electronic properties of nanostructure architectures. Int. J. Comput. Sci. Eng. 2 (3/4) (2006)
Alfredo Buttari, Jack J. Dongarra, Jakub Kurzak, Julie Langou, Julien Langou, Piotr Luszczek, Stanimire Tomov
Exploiting Mixed Precision Floating Point Hardware in Scientific Computations. High Performance Computing Workshop (2006)
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
Self-adapting numerical software (SANS) effort. IBM J. Res. Dev. 50 (2-3) (2006)
Alicja Smoktunowicz, Jesse L. Barlow, Julien Langou
A note on the error analysis of classical Gram-Schmidt. Numerische Mathematik 105 (2) (2006)
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
Prospectus for the Next LAPACK and ScaLAPACK Libraries. PARA (2006)
Alfredo Buttari, Jack J. Dongarra, Jakub Kurzak, Julien Langou, Piotr Luszczek, Stanimire Tomov
The Impact of Multicore on Math Software. PARA (2006)
Julien Langou, George Bosilca, Graham E. Fagg, Jack J. Dongarra
Hash Functions for Datatype Signatures in MPI. PVM/MPI (2005)
Valérie Frayssé, Luc Giraud, Serge Gratton, Julien Langou
Algorithm 842: A set of GMRES routines for real and complex arithmetics on high performance computers. ACM Trans. Math. Softw. 31 (2) (2005)
Stanimire Tomov, Julien Langou, Andrew Canning, Lin-Wang Wang, Jack J. Dongarra
Comparison of Nonlinear Conjugate-Gradient Methods for Computing the Electronic Properties of Nanostructure Architectures. International Conference on Computational Science (3) (2005)
Zizhong Chen, Graham E. Fagg, Edgar Gabriel, Julien Langou, Thara Angskun, George Bosilca, Jack J. Dongarra
Fault tolerant high performance computing by a coding approach. PPOPP (2005)
Luc Giraud, Julien Langou, Miroslav Rozlozník, Jasper van den Eshof
Rounding error analysis of the classical Gram-Schmidt orthogonalization process. Numerische Mathematik 101 (1) (2005)
Luc Giraud, Serge Gratton, Julien Langou
Update Procedure for Reorthogonalizing the Orthogonal Factor from Modified Gram-Schmidt. SIAM J. Matrix Anal. Appl. 25 (4) (2004)
Luc Giraud, Julien Langou
A Robust Criterion for the Modified Gram-Schmidt Algorithm with Selective Reorthogonalization. SIAM J. Sci. Comput. 25 (2) (2003)