trilinos/Trilinos
Aug 2024 – Jun 2026
23 Months active
Languages Used
C++CCMakeMarkdown
Technical Skills
C++algorithm designhigh-performance computingparallel computingC++ developmentCode Cleanup
iyamazaki
PROFILE
Iyamazaki
Over 23 months, contributed to the trilinos/Trilinos repository by engineering scalable, high-performance linear algebra solvers and enhancing distributed computing workflows. Focused on C++ and CUDA, the work included implementing advanced matrix reindexing, parallelization, and memory management strategies to improve solver efficiency and reliability on both CPUs and GPUs. Integrated Kokkos and OpenMP for portable parallelism, expanded support for complex arithmetic, and optimized data movement using template metaprogramming. Addressed robustness through targeted error handling and comprehensive testing, while maintaining code quality via refactoring and documentation. These efforts enabled robust, maintainable solver stacks for large-scale scientific and engineering simulations.
Overall Statistics
Feature vs Bugs
70%Features
Repository Contributions
122Total
Bugs
22
Commits
122
Features
51
Lines of code
41,349
Activity Months23
Your Network
155 peopleSame Organization
@sandia.gov78
Work History
June 2026
2 Commits • 2 Features
Jun 1, 2026Concise monthly summary for 2026-06 focusing on key business value, technical achievements, and measurable impact for trilinos/Trilinos. This period delivered two major features in Trilinos, with improvements in performance, portability, and code quality that enable broader usage and faster, GPU-accelerated solutions.
2 Commits • 2 Features
Jun 1, 2026Concise monthly summary for 2026-06 focusing on key business value, technical achievements, and measurable impact for trilinos/Trilinos. This period delivered two major features in Trilinos, with improvements in performance, portability, and code quality that enable broader usage and faster, GPU-accelerated solutions.
June 2026
May 2026
3 Commits • 2 Features
May 1, 2026May 2026 performance summary for trilinos/Trilinos focusing on delivering scalable sparse linear algebra capabilities and improving maintainability.
May 2026
3 Commits • 2 Features
May 1, 2026May 2026 performance summary for trilinos/Trilinos focusing on delivering scalable sparse linear algebra capabilities and improving maintainability.
April 2026
1 Commits
Apr 1, 2026April 2026 monthly summary for trilinos/Trilinos: Delivered a focused set of numerical robustness and boundary-handling fixes in the FROSch component to improve stability of simulations involving Dirichlet boundaries. Implemented default tolerance for FindOneEntryOnlyRowsGlobal set to zero, refined Dirichlet boundary degree-of-freedom handling, and added presence checks for basis functions. Consolidated into a cohesive patch set associated with commit 2242ca76392d10961e367d5b55ab10976a8d761f and related changes. These changes improved numerical reliability, boundary processing, and maintainability in core solver components.
1 Commits
Apr 1, 2026April 2026 monthly summary for trilinos/Trilinos: Delivered a focused set of numerical robustness and boundary-handling fixes in the FROSch component to improve stability of simulations involving Dirichlet boundaries. Implemented default tolerance for FindOneEntryOnlyRowsGlobal set to zero, refined Dirichlet boundary degree-of-freedom handling, and added presence checks for basis functions. Consolidated into a cohesive patch set associated with commit 2242ca76392d10961e367d5b55ab10976a8d761f and related changes. These changes improved numerical reliability, boundary processing, and maintainability in core solver components.
April 2026
March 2026
1 Commits
Mar 1, 2026March 2026 contributions focused on improving robustness and reliability of numerical solver workflows in trilinos/Trilinos. A targeted bug fix enhances error handling and failure signaling in the Amesos2 solver, enabling clearer downstream decisions and reducing silent failures.
March 2026
1 Commits
Mar 1, 2026March 2026 contributions focused on improving robustness and reliability of numerical solver workflows in trilinos/Trilinos. A targeted bug fix enhances error handling and failure signaling in the Amesos2 solver, enabling clearer downstream decisions and reducing silent failures.
February 2026
3 Commits • 3 Features
Feb 1, 2026February 2026 monthly summary for trilinos/Trilinos: Delivered three key features emphasizing device-level performance, numerical method robustness, and solver observability. No major bug fixes reported this month. Overall impact includes improved device kernel efficiency, enhanced LDL diagonal shift handling, and expanded solver diagnostics for Amesos2, contributing to better performance, stability, and debugging capabilities. Technologies demonstrated include C++/Kokkos-based optimization patterns, numerical linear algebra routines, and tool-assisted configuration visibility.
3 Commits • 3 Features
Feb 1, 2026February 2026 monthly summary for trilinos/Trilinos: Delivered three key features emphasizing device-level performance, numerical method robustness, and solver observability. No major bug fixes reported this month. Overall impact includes improved device kernel efficiency, enhanced LDL diagonal shift handling, and expanded solver diagnostics for Amesos2, contributing to better performance, stability, and debugging capabilities. Technologies demonstrated include C++/Kokkos-based optimization patterns, numerical linear algebra routines, and tool-assisted configuration visibility.
February 2026
January 2026
8 Commits • 5 Features
Jan 1, 2026January 2026 — Consolidated the Amesos2 codepath to a Tpetra-only stack by removing Epetra dependencies and tests, simplifying maintenance and reducing cross-library risks. Introduced performance visibility and stability enhancements: Superlu timer, memory-management improvements, and verbose timing controls. Improved demonstrations and compatibility: added a Tacho outer iteration loop and corrected SimpleSolve_File output; implemented SuperLU_DIST version checks for integer types and expanded unit tests for Superludist and adjusted Tacho performance parameters. Overall impact: lower maintenance burden, clearer performance signals, and more robust solver integration across the Trilinos solver stack.
January 2026
8 Commits • 5 Features
Jan 1, 2026January 2026 — Consolidated the Amesos2 codepath to a Tpetra-only stack by removing Epetra dependencies and tests, simplifying maintenance and reducing cross-library risks. Introduced performance visibility and stability enhancements: Superlu timer, memory-management improvements, and verbose timing controls. Improved demonstrations and compatibility: added a Tacho outer iteration loop and corrected SimpleSolve_File output; implemented SuperLU_DIST version checks for integer types and expanded unit tests for Superludist and adjusted Tacho performance parameters. Overall impact: lower maintenance burden, clearer performance signals, and more robust solver integration across the Trilinos solver stack.
December 2025
6 Commits • 3 Features
Dec 1, 2025Monthly performance summary for 2025-12 focusing on delivering portable, maintainable solver-stack improvements and notable feature delivery in Trilinos/Trilinos.
6 Commits • 3 Features
Dec 1, 2025Monthly performance summary for 2025-12 focusing on delivering portable, maintainable solver-stack improvements and notable feature delivery in Trilinos/Trilinos.
December 2025
November 2025
3 Commits • 1 Features
Nov 1, 2025November 2025 monthly summary for Trilinos/Trilinos focused on delivering unified solver enhancements across Tacho, ShyLU, and Amesos2, reinforced by documentation and release notes to improve stability, performance, and backend clarity. The work emphasizes numerical stability, parallel scalability, and maintainability to deliver tangible business value for large-scale simulations.
November 2025
3 Commits • 1 Features
Nov 1, 2025November 2025 monthly summary for Trilinos/Trilinos focused on delivering unified solver enhancements across Tacho, ShyLU, and Amesos2, reinforced by documentation and release notes to improve stability, performance, and backend clarity. The work emphasizes numerical stability, parallel scalability, and maintainability to deliver tangible business value for large-scale simulations.
October 2025
3 Commits • 3 Features
Oct 1, 2025October 2025: Delivered measurable improvements in performance visibility, solver coverage, and robustness across Trilinos components. Key efforts included instrumentation for GPU-accelerated paths, expanded LDLt support, and enhanced fallback/recovery in Cholesky, with targeted correctness fixes in examples to improve user experience. These changes enable faster diagnosis, easier adoption of advanced solvers, and more reliable numerical results in production workflows.
3 Commits • 3 Features
Oct 1, 2025October 2025: Delivered measurable improvements in performance visibility, solver coverage, and robustness across Trilinos components. Key efforts included instrumentation for GPU-accelerated paths, expanded LDLt support, and enhanced fallback/recovery in Cholesky, with targeted correctness fixes in examples to improve user experience. These changes enable faster diagnosis, easier adoption of advanced solvers, and more reliable numerical results in production workflows.
October 2025
September 2025
4 Commits • 1 Features
Sep 1, 2025Monthly summary for 2025-09 focusing on Trilinos/Tacho work. Highlights include stability improvements and feature additions across the Tacho component, with emphasis on parallel robustness and user-configurable graph algorithms. All work aligns with delivering stable, scalable solutions for high-performance computing workflows, reducing risk in initialization, matrix allocations, and compiler warnings while enabling user-driven algorithm selection.
September 2025
4 Commits • 1 Features
Sep 1, 2025Monthly summary for 2025-09 focusing on Trilinos/Tacho work. Highlights include stability improvements and feature additions across the Tacho component, with emphasis on parallel robustness and user-configurable graph algorithms. All work aligns with delivering stable, scalable solutions for high-performance computing workflows, reducing risk in initialization, matrix allocations, and compiler warnings while enabling user-driven algorithm selection.
August 2025
5 Commits • 3 Features
Aug 1, 20252025-08 monthly summary for trilinos/Trilinos: Delivered solver and parallelization enhancements across Amesos2, Stratimikos, and ShyLU-Basker; expanded mixed-precision support and added tests to validate end-to-end functionality, driving broader solver coverage, performance, and reliability in production workloads.
5 Commits • 3 Features
Aug 1, 20252025-08 monthly summary for trilinos/Trilinos: Delivered solver and parallelization enhancements across Amesos2, Stratimikos, and ShyLU-Basker; expanded mixed-precision support and added tests to validate end-to-end functionality, driving broader solver coverage, performance, and reliability in production workloads.
August 2025
July 2025
1 Commits • 1 Features
Jul 1, 2025Monthly work summary for 2025-07 focusing on Trilinos/Tacho work. Key feature delivered: Tacho Solver Deprecated Parameter Removal and Improved User Feedback; commits include e9434100a1c2b074c263ffe7b83e999a9197e5ae. Major bugs fixed: none reported in scope of this work. Overall impact: improved maintainability and user experience by aligning Tacho with current configurations and cleaning up deprecated parameters. Technologies/skills demonstrated: C++ build-time feature toggling (conditional compilation), API deprecation handling, enhanced user-facing messaging, and documentation of changes in example drivers.
July 2025
1 Commits • 1 Features
Jul 1, 2025Monthly work summary for 2025-07 focusing on Trilinos/Tacho work. Key feature delivered: Tacho Solver Deprecated Parameter Removal and Improved User Feedback; commits include e9434100a1c2b074c263ffe7b83e999a9197e5ae. Major bugs fixed: none reported in scope of this work. Overall impact: improved maintainability and user experience by aligning Tacho with current configurations and cleaning up deprecated parameters. Technologies/skills demonstrated: C++ build-time feature toggling (conditional compilation), API deprecation handling, enhanced user-facing messaging, and documentation of changes in example drivers.
June 2025
3 Commits • 2 Features
Jun 1, 2025June 2025 monthly summary for trilinos/Trilinos focusing on performance, data input flexibility, and reliability enhancements across the Tacho and Amesos2 interfaces. Deliverables emphasize business value through data-driven performance analysis, reproducible solver experiments, and robust error handling.
3 Commits • 2 Features
Jun 1, 2025June 2025 monthly summary for trilinos/Trilinos focusing on performance, data input flexibility, and reliability enhancements across the Tacho and Amesos2 interfaces. Deliverables emphasize business value through data-driven performance analysis, reproducible solver experiments, and robust error handling.
June 2025
May 2025
2 Commits • 1 Features
May 1, 2025May 2025 performance summary for trilinos/Trilinos focused on scalable solver improvements, robustness, and cross-library collaboration. Delivered substantial threading-enabled enhancements for the ShyLU-Basker solver, improved conformance for threading in core solve paths, and hardened components against edge-case failures. These changes elevate concurrency, reduce solve times for large-scale problems, and increase reliability in production workflows.
May 2025
2 Commits • 1 Features
May 1, 2025May 2025 performance summary for trilinos/Trilinos focused on scalable solver improvements, robustness, and cross-library collaboration. Delivered substantial threading-enabled enhancements for the ShyLU-Basker solver, improved conformance for threading in core solve paths, and hardened components against edge-case failures. These changes elevate concurrency, reduce solve times for large-scale problems, and increase reliability in production workflows.
April 2025
4 Commits • 2 Features
Apr 1, 2025April 2025 monthly summary for trilinos/Trilinos focusing on performance and reliability improvements in Amesos2 with SuperLU_DIST and Tacho, delivering robust GID handling, safer host-device data lifetimes, and expanded complex-number support. These changes improve solver robustness, data compatibility, and test coverage, enabling more reliable deployments and performance on leadership-scale simulations.
4 Commits • 2 Features
Apr 1, 2025April 2025 monthly summary for trilinos/Trilinos focusing on performance and reliability improvements in Amesos2 with SuperLU_DIST and Tacho, delivering robust GID handling, safer host-device data lifetimes, and expanded complex-number support. These changes improve solver robustness, data compatibility, and test coverage, enabling more reliable deployments and performance on leadership-scale simulations.
April 2025
March 2025
5 Commits • 3 Features
Mar 1, 2025March 2025: Delivered improvements across testing reliability, numerical robustness, and HIP-enabled performance pathways in Trilinos. Key features and fixes include refactoring the Teuchos Scatterv unit test to use Teuchos::dyn_cast for MpiComm and removing a stale test instantiation to simplify the suite; ShyLU-Basker robustness improvements covering type consistency, complex float/double support, and transitions from assertions to exceptions to improve reliability and configurability; and the Tacho solver enhancement introducing an explicit transpose storage option with HIP gating and CLI exposure, including driver and test updates. These changes strengthen test coverage, broaden support for complex-valued problems, enable HIP-based builds, and reduce maintenance risk, contributing to more reliable numerical workflows and faster issue resolution.
March 2025
5 Commits • 3 Features
Mar 1, 2025March 2025: Delivered improvements across testing reliability, numerical robustness, and HIP-enabled performance pathways in Trilinos. Key features and fixes include refactoring the Teuchos Scatterv unit test to use Teuchos::dyn_cast for MpiComm and removing a stale test instantiation to simplify the suite; ShyLU-Basker robustness improvements covering type consistency, complex float/double support, and transitions from assertions to exceptions to improve reliability and configurability; and the Tacho solver enhancement introducing an explicit transpose storage option with HIP gating and CLI exposure, including driver and test updates. These changes strengthen test coverage, broaden support for complex-valued problems, enable HIP-based builds, and reduce maintenance risk, contributing to more reliable numerical workflows and faster issue resolution.
February 2025
28 Commits • 7 Features
Feb 1, 2025February 2025 (2025-02) consolidated a strong set of feature deliveries and stability fixes across the Trilinos stack, with a clear emphasis on expanding vector operations, gather/scatter patterns, and test coverage for real-world matrices. The work delivered robust vector-gather capabilities for Amesos2 across Tpetra and Epetra, enhanced gathering with custom options and multi-vector support, and improved solver visibility via debug logging and shadow-variable fixes in ShyLU-Basker. Additional features broadened test coverage and numerical support, including Teuchos scatterv for double/float and Tacho LevelSet with Serial build and unit-test variants, complemented by targeted bug fixes that reduce risk on rectangular matrices, host/device access, and OpenMP paths. Overall, these efforts increase solver compatibility, reliability, and maintainability, delivering tangible business value for production workloads that involve large, diverse sparse matrices.
28 Commits • 7 Features
Feb 1, 2025February 2025 (2025-02) consolidated a strong set of feature deliveries and stability fixes across the Trilinos stack, with a clear emphasis on expanding vector operations, gather/scatter patterns, and test coverage for real-world matrices. The work delivered robust vector-gather capabilities for Amesos2 across Tpetra and Epetra, enhanced gathering with custom options and multi-vector support, and improved solver visibility via debug logging and shadow-variable fixes in ShyLU-Basker. Additional features broadened test coverage and numerical support, including Teuchos scatterv for double/float and Tacho LevelSet with Serial build and unit-test variants, complemented by targeted bug fixes that reduce risk on rectangular matrices, host/device access, and OpenMP paths. Overall, these efforts increase solver compatibility, reliability, and maintainability, delivering tangible business value for production workloads that involve large, diverse sparse matrices.
February 2025
January 2025
18 Commits • 5 Features
Jan 1, 2025January 2025 performance summary for trilinos/Trilinos focused on robustness, testing, and solver workflow improvements. Key features delivered include Amesos2 core robustness and gather improvements, Galeri-based testing integration, and enhancements to SimpleSolve_File. Additionally, OpenMP-enabled improvements and memory/workspace optimizations were implemented in Tacho, symbolic ND ordering support in ShyLU-Basker, and targeted fixes to bolster overall solver reliability. Major bugs fixed included fixed zero-based gather indexing for TpetraCrsMatrix, enhanced error propagation in SuperLU equilibration, and a rollback to stabilize Galeri/gather changes. The month culminated in stronger solver stability, expanded testing coverage, and clearer error handling across the Amesos2/SolverCore stack, benefiting reliability and scalability of large-scale simulations.
January 2025
18 Commits • 5 Features
Jan 1, 2025January 2025 performance summary for trilinos/Trilinos focused on robustness, testing, and solver workflow improvements. Key features delivered include Amesos2 core robustness and gather improvements, Galeri-based testing integration, and enhancements to SimpleSolve_File. Additionally, OpenMP-enabled improvements and memory/workspace optimizations were implemented in Tacho, symbolic ND ordering support in ShyLU-Basker, and targeted fixes to bolster overall solver reliability. Major bugs fixed included fixed zero-based gather indexing for TpetraCrsMatrix, enhanced error propagation in SuperLU equilibration, and a rollback to stabilize Galeri/gather changes. The month culminated in stronger solver stability, expanded testing coverage, and clearer error handling across the Amesos2/SolverCore stack, benefiting reliability and scalability of large-scale simulations.
December 2024
12 Commits • 3 Features
Dec 1, 2024December 2024 monthly summary for trilinos/Trilinos. This period focused on delivering cross-backend enhancements, strengthening device support, and tightening maintenance for Amesos2 and Tacho. The work expanded capabilities for Epetra/Tpetra backends, improved reliability of factorization workflows on accelerators, and reduced maintenance overhead through cleanup and clearer documentation. Business value is reflected in broader compatibility, more robust numerical routines, and clearer testing/documentation pipelines.
12 Commits • 3 Features
Dec 1, 2024December 2024 monthly summary for trilinos/Trilinos. This period focused on delivering cross-backend enhancements, strengthening device support, and tightening maintenance for Amesos2 and Tacho. The work expanded capabilities for Epetra/Tpetra backends, improved reliability of factorization workflows on accelerators, and reduced maintenance overhead through cleanup and clearer documentation. Business value is reflected in broader compatibility, more robust numerical routines, and clearer testing/documentation pipelines.
December 2024
November 2024
4 Commits • 1 Features
Nov 1, 2024November 2024 monthly summary for trilinos/Trilinos: Delivered targeted memory management and reliability improvements that enhance robustness, efficiency, and stability across solver components. Key work focused on ShyLU Basker memory pre-allocation with a new PREORDERING phase to improve allocation accuracy for off-diagonal and separator blocks, and memory root image handling to boost robustness. Also fixed Tacho reliability issues by resolving an OpenMP compile error in LU::invoke (removing an unused tol parameter) and enforcing a minimum number of streams to prevent zero-stream scenarios. These changes reduce OOM risk, improve solver predictability, and streamline parallel execution, contributing to more reliable deployments and better performance in large-scale runs. Technologies/skills demonstrated include memory management optimization, PREORDERING algorithms, OpenMP-based parallelism, streams management, and cross-component maintenance in Trilinos.
November 2024
4 Commits • 1 Features
Nov 1, 2024November 2024 monthly summary for trilinos/Trilinos: Delivered targeted memory management and reliability improvements that enhance robustness, efficiency, and stability across solver components. Key work focused on ShyLU Basker memory pre-allocation with a new PREORDERING phase to improve allocation accuracy for off-diagonal and separator blocks, and memory root image handling to boost robustness. Also fixed Tacho reliability issues by resolving an OpenMP compile error in LU::invoke (removing an unused tol parameter) and enforcing a minimum number of streams to prevent zero-stream scenarios. These changes reduce OOM risk, improve solver predictability, and streamline parallel execution, contributing to more reliable deployments and better performance in large-scale runs. Technologies/skills demonstrated include memory management optimization, PREORDERING algorithms, OpenMP-based parallelism, streams management, and cross-component maintenance in Trilinos.
October 2024
1 Commits • 1 Features
Oct 1, 2024Month: 2024-10 — Trilinos project delivered a targeted performance optimization in the matrix reindexing workflow. No major bugs reported/fixed this month. Overall impact includes faster matrix reindexing operations, improved maintainability through component reuse, and stronger alignment with existing Amesos2 workflows.
1 Commits • 1 Features
Oct 1, 2024Month: 2024-10 — Trilinos project delivered a targeted performance optimization in the matrix reindexing workflow. No major bugs reported/fixed this month. Overall impact includes faster matrix reindexing operations, improved maintainability through component reuse, and stronger alignment with existing Amesos2 workflows.
October 2024
September 2024
4 Commits • 1 Features
Sep 1, 2024Summary for 2024-09: Delivered Amesos2 Distributed Matrix Reindexing and Mapping Optimization in trilinos/Trilinos. Implemented GO-based global ordinal types for CSS compatibility, added CSS reindexing, and introduced contiguous row/column maps with updated reindexing to improve performance in distributed environments. Included internal code cleanup to improve readability and maintainability. Notable commits: 15146998c37a40f8094e7bde99da9fdca5a930cf, aafc549d77eb5d569da2702eb3d1770749ea3d16, fb9603ade2e83e0c3941864a097353ab668e2c37, 0cb1a4f07eebe908fb23536a66dedfa668c5ee99.
September 2024
4 Commits • 1 Features
Sep 1, 2024Summary for 2024-09: Delivered Amesos2 Distributed Matrix Reindexing and Mapping Optimization in trilinos/Trilinos. Implemented GO-based global ordinal types for CSS compatibility, added CSS reindexing, and introduced contiguous row/column maps with updated reindexing to improve performance in distributed environments. Included internal code cleanup to improve readability and maintainability. Notable commits: 15146998c37a40f8094e7bde99da9fdca5a930cf, aafc549d77eb5d569da2702eb3d1770749ea3d16, fb9603ade2e83e0c3941864a097353ab668e2c37, 0cb1a4f07eebe908fb23536a66dedfa668c5ee99.
August 2024
1 Commits • 1 Features
Aug 1, 2024August 2024 monthly summary for trilinos/Trilinos: Implemented distributed Amesos2 solver enhancements to improve scalability, flexibility, and compatibility in distributed computing environments. This included introducing an option to use Zoltan2 for partitioning in the SimpleSolve_File example and updating the CssMKL interface to support permuted global IDs, enabling better interoperability and performance across distributed runs. The changes reduce setup complexity and improve solver efficiency for large-scale linear solves.
1 Commits • 1 Features
Aug 1, 2024August 2024 monthly summary for trilinos/Trilinos: Implemented distributed Amesos2 solver enhancements to improve scalability, flexibility, and compatibility in distributed computing environments. This included introducing an option to use Zoltan2 for partitioning in the SimpleSolve_File example and updating the CssMKL interface to support permuted global IDs, enabling better interoperability and performance across distributed runs. The changes reduce setup complexity and improve solver efficiency for large-scale linear solves.
August 2024
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Quality Metrics
Correctness85.4%
Maintainability83.0%
Architecture81.6%
Performance77.4%
AI Usage21.8%
Skills & Technologies
Programming Languages
CC++CMakeMarkdown
Technical Skills
Algorithm ImplementationBLASBuild System ConfigurationBuild SystemsC DevelopmentC++C++ DevelopmentC++ Template MetaprogrammingC++ developmentCMakeCMake configurationCUDACode CleanupCode RefactoringCompiler Warnings
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