Run-time Performance Comparison of Sparse-set and Archetype Entity-Component Systems

Entity-Component System (ECS) architectures have emerged as a powerful alternative to traditional object-oriented solutions in video games and real-time simulations. However, different ECS implementations present distinct trade-offs between iteration speed and modification costs. Despite its growing adoption, a comparative analysis on the performance characteristics of ECS implementation types has yet to be conducted. This study compares the performance of two widely-used ECS implementations: sparse-set and archetype-based. To facilitate this, an implementation of each architecture was developed in C++20 and their performance was examined in terms of iteration speed and entity modification costs. The results show sparse-set ECSes enable cheaper entity modifications but scale poorly during iteration, while archetypes excel at large-scale iteration through cache efficiency but incur higher composition change costs. These findings provide valuable and actionable guidance for developers selecting ECS architectures for their specific applications.