Asynchronous pipeline creation is very slow

[Egor Yusov]

Hello!

We are using asynchronous pipeline creation and noticed that it is very slow. Where our native D3D11/D3D12 renderer takes just a few seconds to start, it takes more than a minute for Dawn to compile all pipelines.

It appears it spends most of its time in d3dcompiler_47.dll, which is quite expected, but it does not seem that it performs shader compilation in multiple threads in parallel.

Again, our native D3D11 renderer compiles largely same shaders and with threaded compilation it takes only a few seconds to compile all shaders.

We use D3D12 Dawn backend on Windows 10.

Any suggestion will be highly appreciated.

Thank you,

Egor.