As part of the WebSharper web server effort, I have been writing an HTTP request parser. Tuning the parser for performance for the common simple case (small, correct HTTP request) has improved performance 8-fold, from 30K to 250K sample requests parsed every second on a single core of my Core i3. Let me review what I have learned from this. Indexing Accessing array elements goes through a bounds check. Unmanaged C++ code clearly wins here. C# has unsafe regions, but F# does not. So what can we do in [...]