Microsoft reports 41% fewer allocations and 25% less time in WinUI code for File Explorer launch, with more improvements coming to WinAppSDK 2.x.
Key Takeaways
File Explorer launch benchmarks show 41% fewer allocations, 63% fewer transient allocations, 45% fewer function calls, and 25% less time in WinUI code.
Notepad and File Explorer serve as primary benchmarks; gains are designed to broadly benefit most apps, not just first-party ones.
Some optimizations require opt-in due to breaking changes in control templates or animation-based property setters; opt-out defaults planned for WinUI 3.0 or 4.0+.
Changes will land in winui3/main branch soon; WinAppSDK 2.x backports are planned where risk is acceptable.
Microsoft frames WinUI 3 as the strategic native framework going forward, with performance parity over WinUI 2 as a baseline requirement.
