Build Performance for C++

Analyze MSVC build performance with vcperf.exe and ETL traces from GitHub Copilot CLI.

Features

• Captures diagnostic traces for MSVC builds
• Generates structured /jsonAnalysis reports
• Identifies expensive headers, functions, and template instantiations
• Recommends targeted build-performance improvements
• Measures clean and iterative builds before and after changes

Requirements

• Windows with the MSVC toolchain
• NuGet CLI (nuget.exe) on PATH
• Administrator privileges, or a one-time vcperf /grantusercontrol
• Network access to the public Visual C++ package feed

The session-start hook installs or updates the newest published Microsoft.Cpp.vcperf package under %LOCALAPPDATA%\vcperf\build-perf-cpp.

Install

The copilot-plugins marketplace is registered by default in Copilot CLI:

copilot plugin install build-perf-cpp@copilot-plugins

Use

Start Copilot CLI in an MSVC project and ask:

Improve the build performance of this project.

The build-performance-analysis skill captures a trace, ranks build bottlenecks, recommends changes, and compares uninstrumented before-and-after build measurements.

Hooks

• sessionStart installs or updates vcperf.exe.
• userPromptSubmitted creates a correlation identifier for trace artifacts.

Both hooks operate locally and write only beneath %LOCALAPPDATA%\vcperf.

Contributors

• Ion Todirel
• Eve Silfanus