Hemlok

A small sampling profiler for Linux. Point it at an executable, run it, and see where the time went.

Build and run

Requires Linux, CMake 3.20+, a C++23 compiler, and OpenGL.

cmake -S . -B build
cmake --build build
./build/hemlok

Sampling uses perf_event_open, so unprivileged users need kernel.perf_event_paranoid set to 2 or lower:

sudo sysctl -w kernel.perf_event_paranoid=2

Limitations

• Single-threaded programs only.
• Flat, per-function view; no call stacks.
• Functions from stripped libraries show up as [unknown].

Development

ctest --test-dir build --output-on-failure   # run tests
./scripts/format.sh                          # format sources
git config core.hooksPath .githooks          # check formatting on commit

CI builds and tests on Ubuntu and checks formatting on every push and pull request to main.

License

MIT