Making PLUMED Fly: A Tutorial on Optimizing Performance.

Area of Science:

• Computational Chemistry
• Molecular Dynamics Simulations
• Bioinformatics

Background:

• PLUMED is a widely used open-source package for molecular dynamics (MD) simulations.
• Increasingly complex descriptors in PLUMED necessitate performance optimization.
• Existing computational costs for complex descriptors can be substantial.

Purpose of the Study:

• To introduce a new tool for reliably measuring PLUMED code performance.
• To provide detailed performance benchmarks for optimizing PLUMED calculations.
• To explain algorithmic optimizations for broader user adoption.

Main Methods:

• Implementation of a performance measurement tool within PLUMED.
• Generation of performance benchmarks for various PLUMED calculations.
• Analysis of computational strategies, comparing vector-based vs. scalar operations.

Main Results:

• Demonstrated optimization of large-number calculations (distances, angles, torsions) using vector commands.
• Presented benchmarks for optimizing atomic order parameters and secondary structure variables.
• Quantified performance improvements through specific algorithmic techniques.

Conclusions:

• The new performance tool enables reliable code measurement.
• Vector-based commands offer significant optimization for specific calculations.
• Understanding and applying algorithmic tricks can enhance PLUMED's computational efficiency for complex simulations.