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Publications

Architectural efficiency of the miniBUDE mini-app implemented using different programming models on a variety of CPU and GPU architectures

Performance Portability of the Chapel Language on Heterogeneous Architectures

Conference Articles
Josh Milthorpe, Xianghao Wang, Ahmad Azizi
Heterogeneity in Computing Workshop
Publication year: 2024
Performance of PaRSEC Block-Sparse General Matrix Multiply benchmark with and without migration, without load-based task mapping, with both epilogue completion and migration delegated to co-manager. Matrix A with dimensions 20k × 200k with tile size 200 × 200. Matrix B of dimension 20k × 800k with tile size 200×8k. Both matrix A and B have a density of 30% (Synthetic Benchmark).

Multi-Gpu Work Sharing in a Task-Based Dataflow Programming Model

Journal Articles
Joseph John, Josh Milthorpe, Thomas Herault, George Bosilca
Future Generation Computer Systems
Publication year: 2024
Ready tasks available for the Cholesky factorization benchmark

Elasticity in a Task-based Dataflow Runtime Through Inter-node GPU Work Stealing

Conference Articles
Joseph John, Josh Milthorpe
IEEE/ACM international Symposium on Cluster, Cloud and Internet Computing (CCGRID)
Publication year: 2024

Dagster: Parallel Structured Search

Conference Articles
Mark Alexander Burgess, Charles Gretton, Josh Milthorpe, Luke Croak, Thomas Willingham, Alwen Tiu
AAAI Conference on Artificial Intelligence
Publication year: 2023

Accelerating Data Analytics with Arkouda on GPUs

Conference Articles
Josh Milthorpe, Brett Eiffert, and Jeffrey S. Vetter
Chapel Implementers and Users Workshop 2023
Publication year: 2023
Diagram of tasks in a stencil computation, showing critical path in red and independent set for one stage of the computation in green

Distributed Work Stealing in a Task-Based Dataflow Runtime

Conference Articles
Joseph John, Josh Milthorpe, Peter Strazdins
International Conference on Parallel Processing and Applied Mathematics (PPAM)
Publication year: 2022
Dagster's branching search: Illustration of worker backtracking search with SLS suggestion processes set to work constrained from partial assignments at various depths in the search branch (blue dashed lines), shown are previously explored branches (gray) and prohibited decisions arising from conflicts (red crosses)

Dagster: Parallel Structured Search with Case Studies

Conference Articles
Mark Alexander Burgess, Charles Gretton, Josh Milthorpe, Luke Croak, Thomas Willingham, Alwen Tiu
Pacific Rim International Conference on Artificial Intelligence (PRICAI)
Publication year: 2022
distributed reduce kernel example from ArrayChannels.jl paper: reduction occurs in stages occuring at different compute nodes for improved parallelism

Locality-Aware Message Passing with ArrayChannels.jl

Conference Articles
Rohan McLure, Josh Milthorpe
JuliaCon 2020
Publication year: 2020
Status of SYCL implementations (Oct 2020). Four major implementations: DPC++ (Intel oneAPI); ComputeCPP (codeplay); triSYCL (XILINX); hipSYCL (Universitaet Heidelberg)

Evaluating the Performance and Portability of Contemporary SYCL Implementations

Conference Articles
Beau Johnston, Jeffrey S. Vetter, Josh Milthorpe
International Workshop on Performance Portability and Productivity (P3HPC)
Publication year: 2020
Parallel spatial locality metric for selected OpenDwarfs benchmark kernels

Characterizing Optimizations to Memory Access Patterns using Architecture-Independent Program Features

Conference Articles
Aditya Chilukuri, Josh Milthorpe, Beau Johnston
International Workshop on OpenCL, SYCL, Vulkan and SPIR-V (IWOCL)
Publication year: 2020
Diagram of fork and join signals for message-optimal resilient async-finish termination detection

Resilient Optimistic Termination Detection for the Async-Finish Model

Conference Articles
Sara S. Hamouda, Josh Milthorpe
ISC-High Performance (ISC-HPC 2019)
Publication year: 2019
X10 Resilient Iterative Application Framework

Failure Recovery in Resilient X10

Journal Articles
David Grove, Sara S. Hamouda, Benjamin Herta, Arun Iyengar, Kiyokuni Kawachiya, Josh Milthorpe, Vijay Saraswat, Avraham Shinnar, Mikio Takeuchi, Olivier Tardieu
ACM Transactions on Programming Languages and Systems (TOPLAS) 41 (3), 15
Publication year: 2019

OpenCL Performance Prediction using Architecture-Independent Features

Conference Articles
Beau Johnston, Greg Falzon, Josh Milthorpe
International Workshop on High Performance and Dynamic Reconfigurable Systems and Networks (DRSN-2018)
Publication year: 2018
Plot of benchmark kernel execution energy (large problem size) on Corei7-6700K and Nvidia GTX1080

Dwarfs on Accelerators: Enhancing OpenCL Benchmarking for Heterogeneous Computing Architectures

Conference Articles
Beau Johnston, Josh Milthorpe
47th International Conference on Parallel Processing Companion (ICCP'18)
Publication year: 2018
Radar plot of AIWC features for the LUD perimeter kernel

AIWC: OpenCL-based Architecture-Independent Workload Characterization

Conference Articles
Beau Johnston, Josh Milthorpe
The Fifth Workshop on the LLVM Compiler Infrastructure in HPC (LLVM-HPC2018)
Publication year: 2018
Diagram of X10 places executing a resilient computation in which place 2 fails after a checkpoint

Resilient X10 over MPI User Level Failure Mitigation

Conference Articles
Sara S. Hamouda, Benjamin Herta, Josh Milthorpe, David Grove, Olivier Tardieu
ACM SIGPLAN Workshop on X10
Publication year: 2016
Image of part of grammar for user-defined control structure

Control Structure Overloading in X10

Conference Articles
Louis Mandel, Josh Milthorpe, Olivier Tardieu
ACM SIGPLAN Workshop on X10
Publication year: 2016
Plot of locality of integral calculation in Hartree-Fock code

X10 for High Performance Scientific Computing

Preprint & Other
Josh Milthorpe
Ph.D. Thesis, Research School of Computer Science, Australian National University
Publication year: 2015
Test error - training time tradeoff curve for 1-softsync training protocol in Rudra distributed deep neural neural network framework

Model Accuracy and Runtime Tradeoff in Distributed Deep Learning

Preprint & Other
Suyog Gupta, Wei Zhang, Josh Milthorpe
arXiv:1509.04210 [stat.ML]
Publication year: 2015
Parallel code for dense matrix multiplication using 'foreach'

Local Parallel Iteration in X10

Conference Articles
Josh Milthorpe
ACM SIGPLAN Workshop on X10
Publication year: 2015
Summary image of LULESH application including Sedov blast wave, staggered mesh approximation, and scaling plot of X10 vs reference implementation

Exploring the APGAS Programming Model using the LULESH Proxy Application

Preprint & Other
Josh Milthorpe, David Grove, Benjamin Herta, Olivier Tardieu
Technical Report, IBM Research RC25555 (WAT1509-050)
Publication year: 2015
APGAS Scala code for K-Means clustering

Distributed Programming in Scala with APGAS

Conference Articles
Philippe Suter, Olivier Tardieu, Josh Milthorpe
ACM SIGPLAN Symposium on Scala
Publication year: 2015
Failure of an X10 place containing part of a distributed vector, causing loss of data

A Resilient Framework for Iterative Linear Algebra Applications in X10

Conference Articles
Sara S. Hamouda, Josh Milthorpe, Peter E. Strazdins, Vijay Saraswat
16th IEEE International Workshop on Parallel and Distributed Scientific and Engineering Computing (PDSEC)
Publication year: 2015
Performance of X10 High-Performance Linpack benchmark on Power 775

Supporting Array Programming in X10

Conference Articles
David Grove, Josh Milthorpe, Olivier Tardieu
ACM SIGPLAN International Workshop on Libraries, Languages, and Compilers for Array Programming
Publication year: 2014
Resolution of the Operator: block pattern of distributed computation of contributions to the exchange matrix

Resolutions of the Coulomb operator: VIII. Parallel implementation using the modern programming language X10

Journal Articles
Taweetham Limpanuparb, Josh Milthorpe, Alistair P. Rendell
Journal of Computational Chemistry
Publication year: 2014
Magnitude of calculated and reference values of Associated Legendre Polynomials, l=1000

Associated Legendre Polynomials and Spherical Harmonics Computation for Chemistry Applications

Preprint & Other
Taweetham Limpanuparb, Josh Milthorpe
arXiv preprint arXiv:1410.1748
Publication year: 2014
Resolution of long-range Ewald operator into a sum of products of one-electron auxiliary integrals

Resolutions of the Coulomb Operator: VII. Evaluation of Long-Range Coulomb and Exchange Matrices

Journal Articles
Taweetham Limpanuparb, Josh Milthorpe, Alistair P. Rendell, Peter M.W. Gill
Journal of Chemical Theory and Computation 9(2), 863--867
Publication year: 2013
Fourier transform-ion cyclotron resonance mass spectrometer simulation using PGAS-FMM

PGAS-FMM: Implementing a distributed fast multipole method using the X10 programming language

Journal Articles
Josh Milthorpe, Alistair P. Rendell, Thomas Huber
Concurrency and Computation: Practice and Experience
Publication year: 2013
Ghost update put algorithm in two dimensions

Efficient update of ghost regions using active messages

Conference Articles
Josh Milthorpe, Alistair P Rendell
International Conference on High Performance Computing (HiPC)
Publication year: 2012
Division of simulation space into octree for Fast Multiple Method

X10 as a parallel language for scientific computation: practice and experience

Conference Articles
Josh Milthorpe, V. Ganesh, Alistair P. Rendell, David Grove
IEEE International Parallel and Distributed Processing Symposium
Publication year: 2011

Interval Arithmetic and Computational Science: Rounding and Truncation Errors in N-Body Methods

Conference Articles
Alistair P. Rendell, Bill Clarke, Pete Janes, Josh Milthorpe, Rui Yang
International Conference on Computational Science and its Applications (ICCSA)
Publication year: 2007

Interval arithmetic and computational science: performance considerations

Conference Articles
Alistair P. Rendell, Bill Clarke, Josh Milthorpe
International Conference on Computational Science (ICCS)
Publication year: 2006

Using Interval Analysis to Bound Numerical Errors in Scientific Computing

Preprint & Other
Josh Milthorpe
Honours Thesis, Australian National University
Publication year: 2005

Learning to live with errors: a fresh look at floating-point computation

Conference Articles
Josh Milthorpe, Alistair P. Rendell
Australian Undergraduate Students' Computing Conference
Publication year: 2005