profiling

https://github.com/brendangregg/FlameGraph

Pyroscope server should respect request context. If a client cancels a request or it's timed out, any related activity (such as an expensive query) must be cancelled immediately.

For C projects, it would be very useful to have a C API for Vulkan and OpenGL. I'm unsure how feasible this is for DirectX 12 though.

There are many instances of INSTR_CREATE macro documentation saying things like this:

* \param dc  The void * dcontext used to allocate memory for the instr_t.

That should have a # to link up the instr_t type.

Only on first load do we show a loading animation, not on subsequent ones, this should be fixed.