Very interesting, but seems to be focussed on games / frame-based simulations. Does anyone know a similar generic graphical profiler for Linux that also provides system context (other threads, syscalls, preemptions)? I'm only aware of VTune.

Check out Tracy[1]. If you run it as root, it provides a lot of "extra" information, such as when your threads get moved between CPUs. Actually, I saw this post and thought "why should I bother when I already have Tracy?" If anyone has an answer to that, I'm curious to know (:

Tracy is still a frame-based profiler, though.

If you want general system-wide profiling more focused on throughput rather than latency, then I've had a good experience generating flame graphs[2] using plain Linux perf.

[1] https://github.com/wolfpld/tracy

[2] https://www.brendangregg.com/FlameGraphs/cpuflamegraphs.html