Last time i looked Kestrel already uses most of the techniques above ( sans an IOUring backend for Socket ) Almost all allocations are pooled, and zero copy as well.
Header parsing is even done with System.Runtime.Intrinsics using SIMD where possible.
The higher level ASP.NET Core stack is also quite efficient and optimized.
BUT: as soon as you gove above the basic middleware pipeline its tends to get bloated and slow. ASP.NET COre MVC is particulary bad.
System.Text.Json is also quite nice, and often is allocation free.
We bascially just us the middleware pipeline and nothing else, and can get millions of requests per second on basic hardware.
The higher level ASP.NET Core stack is also quite efficient and optimized.
BUT: as soon as you gove above the basic middleware pipeline its tends to get bloated and slow. ASP.NET COre MVC is particulary bad.
System.Text.Json is also quite nice, and often is allocation free.
We bascially just us the middleware pipeline and nothing else, and can get millions of requests per second on basic hardware.