catapult

Slightly off-topic, but the web-based visualization tool - Chromium Catapult's Trace-viewer [0] - used to present the profiling data here is pretty nice I think. The input JSON data format for Trace-viewer is also simple, so it's easy to to leverage it when creating a profiling tool. As a simple example I built a POSIX function call tracer for Linux - cpuusage [1] - which uses it. [0]: https://github.com/catapult-project/catapult/blob/master/tra... [1]: https://github.com/d99kris/cpuusage

A couple of quick notes: * It also writes build output to an output directory * It detects a tty and does the right thing, so on CI you get a linear log * In the output directory it also includes timeline graphs that can be loaded in Chrome's devtools traceview (https://github.com/catapult-project/catapult/blob/master/tra... and in Chrome proper). * The tracing can be viewed live https://buckbuild.com/command/server.html (disclosure: my team created Buck when I was at FB)