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name: platforms-performance description: "Select and diagnose OpenMM runtime platforms, platformProperties, GPU/CPU precision modes, plugin availability, and safe performance tuning." disable-model-invocation: true metadata: disco-role: operating license: MIT, GPL, LGPL

Platforms and Performance

Use this sub-skill when the user needs to choose or troubleshoot an OpenMM Platform, configure platformProperties, verify GPU/CPU availability, or reason about performance diagnostics. Keep production simulation construction in simulation-workflows, force-field/system modeling in force-fields-modeling, custom force or integrator authoring in custom-forces-integrators, and new platform/kernel development in development-extensions.

Quick Routing

• For listing installed platforms, checking package/plugin availability, or verifying a small Context can run, use scripts/check_openmm_platforms.py and the troubleshooting guide.
• For choosing Reference, CPU, CUDA, OpenCL, or HIP, and setting Simulation(..., platform=..., platformProperties=...), read references/platform-selection.md.
• For precision, device selection, CPU threads, determinism, first-run kernel compilation, benchmarks, and PME tuning caveats, read references/performance-and-benchmarking.md.
• For missing CUDA/OpenCL/HIP platforms, driver/package mismatches, plugin directory problems, unsupported properties, and nondeterministic results, read references/troubleshooting.md.

Safe Defaults

• Prefer CUDA or HIP for supported GPUs, OpenCL when that is the available accelerator, CPU for multithreaded CPU runs, and Reference for correctness smoke tests or fallback diagnostics.
• For GPU production runs, start with {"Precision": "mixed"} unless the user explicitly prioritizes maximum throughput over energy conservation or needs full double precision.
• Always provide a graceful fallback path when selecting optional GPU platforms: list available platforms first, then choose the requested platform if present, otherwise fallback to CPU or Reference with a clear warning.
• Do not recommend long benchmarks as routine checks. Use benchmark scripts only as optional, user-approved performance studies after installation and simulation setup already work.

Bundled Files

• references/platform-selection.md: platform inventory, selection examples, platform property matrix, and installation extras.
• references/performance-and-benchmarking.md: precision/performance tradeoffs, benchmark interpretation, PME tuning, and determinism notes.
• references/troubleshooting.md: symptom-oriented fixes for missing platforms, plugin loading, device selection, precision, and runtime performance issues.
• scripts/check_openmm_platforms.py: a lightweight diagnostic script adapted from OpenMM's installation test pattern for safe listing and optional smoke checks.