Over twelve months, Nick Keen engineered robust build, configuration, and testing enhancements for the E3SM-Project/E3SM repository, focusing on high-performance computing and climate modeling workflows. He streamlined cross-platform build systems using CMake and Fortran, standardized compiler flags, and improved GPU and CPU resource management for NERSC and related environments. Nick introduced modular kernel configurations, optimized OpenMP threading, and aligned test suites for reproducibility and performance validation. His work included deprecating obsolete modules, refining parallel computing layouts, and stabilizing CI/CD pipelines. These efforts resulted in a more maintainable, portable codebase with improved simulation fidelity, build reliability, and efficient onboarding for new platforms.
2026-01 Monthly Summary for E3SM: Implemented relocation of OpenMP environment variable settings to a dedicated CPU threading section in the configuration file to improve threading support for CPU builds. This change clarifies threading options and enhances build-time organization, contributing to more reliable performance tuning and reduced risks of misconfiguration during CPU builds. Associated commit: f1c884cac34f76501cb31e3683f724b8636f7ab3 (move OMP section for pm-cpu missed in #7932).
2026-01 Monthly Summary for E3SM: Implemented relocation of OpenMP environment variable settings to a dedicated CPU threading section in the configuration file to improve threading support for CPU builds. This change clarifies threading options and enhances build-time organization, contributing to more reliable performance tuning and reduced risks of misconfiguration during CPU builds. Associated commit: f1c884cac34f76501cb31e3683f724b8636f7ab3 (move OMP section for pm-cpu missed in #7932).
December 2025 monthly summary for the E3SM project (E3SM repository: E3SM-Project/E3SM). Focused on delivering scalable GPU/resource management improvements, stabilizing parallel runtime configurations, and ensuring reproducible builds across HPC environments. The work emphasizes business value through efficient resource usage, improved reliability, and maintainable, portable code across NERSC and related HPC machines.
December 2025 monthly summary for the E3SM project (E3SM repository: E3SM-Project/E3SM). Focused on delivering scalable GPU/resource management improvements, stabilizing parallel runtime configurations, and ensuring reproducible builds across HPC environments. The work emphasizes business value through efficient resource usage, improved reliability, and maintainable, portable code across NERSC and related HPC machines.
November 2025 monthly summary for E3SM: Delivered targeted validation and build reliability improvements. Key work focused on expanding RCS testing coverage and stabilizing the toolchain to reduce build risks, enabling smoother CI and validation cycles for production deployments.
November 2025 monthly summary for E3SM: Delivered targeted validation and build reliability improvements. Key work focused on expanding RCS testing coverage and stabilizing the toolchain to reduce build risks, enabling smoother CI and validation cycles for production deployments.
Monthly summary for Oct 2025 for the E3SM project highlighting key feature deliveries, critical bug fixes, overall impact, and demonstrated technical proficiency. Focused on delivering higher fidelity simulations, stabilizing the test suite under new defaults, and enabling more efficient debugging on HPC resources.
Monthly summary for Oct 2025 for the E3SM project highlighting key feature deliveries, critical bug fixes, overall impact, and demonstrated technical proficiency. Focused on delivering higher fidelity simulations, stabilizing the test suite under new defaults, and enabling more efficient debugging on HPC resources.
Monthly work summary for 2025-09 focused on enabling NVIDIA compiler compatibility for EAMXX and streamlining the build/test configuration in the E3SM repository. The work targeted build reliability, performance-oriented tooling, and maintenance hygiene across pm-cpu and pm-gpu configurations. Key outcomes include the delivery of a new NVIDIA compiler compatible path for EAMXX on pm-cpu and the deprecation of the gcp12 environment with updated module versions, aligning the project with current toolchains and reducing configuration debt.
Monthly work summary for 2025-09 focused on enabling NVIDIA compiler compatibility for EAMXX and streamlining the build/test configuration in the E3SM repository. The work targeted build reliability, performance-oriented tooling, and maintenance hygiene across pm-cpu and pm-gpu configurations. Key outcomes include the delivery of a new NVIDIA compiler compatible path for EAMXX on pm-cpu and the deprecation of the gcp12 environment with updated module versions, aligning the project with current toolchains and reducing configuration debt.
Month: 2025-08 — Focused on cross-platform build reliability and codebase simplification for E3SM. Key features delivered: 1) Stabilized Muller CPU/GPU builds by standardizing compiler flags across machine types and adding an NVIDIA compiler workaround to improve reliability. 2) Deprecation and removal of the evp-patch module to simplify the codebase with minimal user-facing impact. Major bugs fixed: Build-related inconsistencies due to NVIDIA compiler issues across Muller configurations addressed, improving cross-platform build stability. Overall impact and accomplishments: Higher build reliability across CPU/GPU pipelines, reduced maintenance burden from the deprecated module, and a cleaner, more maintainable codebase. Technologies/skills demonstrated: Cross-platform build engineering, compiler flag standardization, debugging NVIDIA compiler issues, codebase cleanup, and module deprecation with traceable commits to support long-term maintenance.
Month: 2025-08 — Focused on cross-platform build reliability and codebase simplification for E3SM. Key features delivered: 1) Stabilized Muller CPU/GPU builds by standardizing compiler flags across machine types and adding an NVIDIA compiler workaround to improve reliability. 2) Deprecation and removal of the evp-patch module to simplify the codebase with minimal user-facing impact. Major bugs fixed: Build-related inconsistencies due to NVIDIA compiler issues across Muller configurations addressed, improving cross-platform build stability. Overall impact and accomplishments: Higher build reliability across CPU/GPU pipelines, reduced maintenance burden from the deprecated module, and a cleaner, more maintainable codebase. Technologies/skills demonstrated: Cross-platform build engineering, compiler flag standardization, debugging NVIDIA compiler issues, codebase cleanup, and module deprecation with traceable commits to support long-term maintenance.
July 2025 performance summary for the E3SM project (E3SM repository). Focused on GPU performance validation and test stability for EAMXX. Delivered two GPU-focused performance test suites (e3sm_eamxx_large and e3sm_eamxx_xlarge) to evaluate EAMXX under large configurations and high node counts on GPU hardware; this enables earlier detection of scaling bottlenecks and helps optimize GPU utilization. Cleaned and stabilized EAMXX test configurations to reduce flaky runs and resource waste: removed a DEBUG ne256 test, renamed xlarge to extra_large, ensured ne120 tests run with 128 vertical levels, and disabled an OOM-prone PEM test to prevent resource errors. These changes improve reliability, reduce wasted compute time, and enhance validation coverage for GPU deployments.
July 2025 performance summary for the E3SM project (E3SM repository). Focused on GPU performance validation and test stability for EAMXX. Delivered two GPU-focused performance test suites (e3sm_eamxx_large and e3sm_eamxx_xlarge) to evaluate EAMXX under large configurations and high node counts on GPU hardware; this enables earlier detection of scaling bottlenecks and helps optimize GPU utilization. Cleaned and stabilized EAMXX test configurations to reduce flaky runs and resource waste: removed a DEBUG ne256 test, renamed xlarge to extra_large, ensured ne120 tests run with 128 vertical levels, and disabled an OOM-prone PEM test to prevent resource errors. These changes improve reliability, reduce wasted compute time, and enhance validation coverage for GPU deployments.
June 2025: Delivered Kokkos Kernel Modularity for alvarez-gpu, aligning with pm-gpu to enable small, non-monolithic kernels across components. This standardizes GPU kernel configuration and prepares the codebase for faster builds, reduced compile-time overhead, and potential performance gains. Major commit: c739c5148057941078b61419b57f22bd57b55449 - "Use small kernels for alvarez-gpu in same way we do for pm-gpu." No major bugs fixed this month; focus was on architectural enhancements, maintainability, and preparing for future performance tuning and scalability in E3SM.
June 2025: Delivered Kokkos Kernel Modularity for alvarez-gpu, aligning with pm-gpu to enable small, non-monolithic kernels across components. This standardizes GPU kernel configuration and prepares the codebase for faster builds, reduced compile-time overhead, and potential performance gains. Major commit: c739c5148057941078b61419b57f22bd57b55449 - "Use small kernels for alvarez-gpu in same way we do for pm-gpu." No major bugs fixed this month; focus was on architectural enhancements, maintainability, and preparing for future performance tuning and scalability in E3SM.
Summary for 2025-05: Delivered cross-platform NE4 configurations and pelayout alignment to enable consistent testing across HPC systems, improved reproducibility of land-ice and EAMXX tests, and reduced configuration clutter. Removed an unused NE30 default to streamline gcp12 configuration. These changes demonstrate strong HPC configuration, EAMXX/pelayout skills, and proactive maintenance that supports faster onboarding of new platforms.
Summary for 2025-05: Delivered cross-platform NE4 configurations and pelayout alignment to enable consistent testing across HPC systems, improved reproducibility of land-ice and EAMXX tests, and reduced configuration clutter. Removed an unused NE30 default to streamline gcp12 configuration. These changes demonstrate strong HPC configuration, EAMXX/pelayout skills, and proactive maintenance that supports faster onboarding of new platforms.
April 2025 focused on strengthening hardware readiness and model fidelity for the E3SM project. Key deliveries include machine-configuration consolidation with CMA set as default on pm-cpu, introduction of NERSC internal alvarez-gpu and alvarez-cpu configurations, and removal of obsolete gcp10/stampede2 configurations. EAM component enhancements and PE layout refactor were implemented, including zm_conv_readnl improvements and moving EAMXX pelayouts to their own file with higher-resolution defaults. A regression fix reverted unintended changes to a file to restore prior behavior and prevent disruption. The overall outcome improves hardware alignment with current/future systems, enhances simulation fidelity, and increases maintainability and reproducibility. Skills demonstrated include configuration management for HPC, EAM parameter handling, PE layout management, and regression handling, all contributing to business value through stability, performance, and easier on-ramping for new hardware.
April 2025 focused on strengthening hardware readiness and model fidelity for the E3SM project. Key deliveries include machine-configuration consolidation with CMA set as default on pm-cpu, introduction of NERSC internal alvarez-gpu and alvarez-cpu configurations, and removal of obsolete gcp10/stampede2 configurations. EAM component enhancements and PE layout refactor were implemented, including zm_conv_readnl improvements and moving EAMXX pelayouts to their own file with higher-resolution defaults. A regression fix reverted unintended changes to a file to restore prior behavior and prevent disruption. The overall outcome improves hardware alignment with current/future systems, enhances simulation fidelity, and increases maintainability and reproducibility. Skills demonstrated include configuration management for HPC, EAM parameter handling, PE layout management, and regression handling, all contributing to business value through stability, performance, and easier on-ramping for new hardware.
March 2025 monthly summary for E3SM (2025-03). Focused on delivering performance-oriented kernel optimizations, build-system robustness, and precision enhancements, while tightening test configurations to improve reliability and reproducibility across PM-CPU/PM-GPU environments. Key work spanned GPU kernel optimization, Fortran/build flag cleanup, numeric precision support, and test layout governance.
March 2025 monthly summary for E3SM (2025-03). Focused on delivering performance-oriented kernel optimizations, build-system robustness, and precision enhancements, while tightening test configurations to improve reliability and reproducibility across PM-CPU/PM-GPU environments. Key work spanned GPU kernel optimization, Fortran/build flag cleanup, numeric precision support, and test layout governance.
February 2025 monthly summary for E3SM project highlighting key deliverables and technical improvements across CPU and GPU workflows. Focused on enabling extensibility, improving performance, and increasing build reliability.
February 2025 monthly summary for E3SM project highlighting key deliverables and technical improvements across CPU and GPU workflows. Focused on enabling extensibility, improving performance, and increasing build reliability.
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