4 ms·

How is this an apples to apples comparison? Instantiating CRTPInterface with Implementation is no different than just calling DynamicImplementation::tick() dire

• Rusky 12y ago
  The entire point of the benchmark is virtual calls vs templated static calls. Everything else is what should be controlled.
  • kazinator 12y ago
    If everything else can be controlled, then virtual calls are being used unnecessarily. The fact that an indirect calling mechanism which has to first use indirection to retrieve the address to be called (and possibly do more work, like fixing up a pointer) is slower than a static call is completely unsurprising. If virtual calls are used essentially, then it's a canoe-versus-bicycle comparison, because everything else cannot be controlled. The program based on static calls has to be written quite differently to solve the same problem, and the benchmark then measures the entire approach. Plus the benchmark doesn't account for benefits that it doesn't measure, like maintainability and extensibility of the code.
    • Rusky 12y ago
      Regardless, it's still useful to actually test the performance of virtual vs static calls- how much slower are they? in which situations can the compiler devirtualize them? Or should we only ever benchmark the entire software stack at once, even though people do in fact sometimes use CRTP and virtual functions in the same situations?
      • bit_razor 12y ago
        My beef with this article is that it misleads you believe that need CRTP is the only way to eliminate vtable lookups on interface calls. It left me wondering how CRTP compared to invoking DynamicImplementation::tick() directly. The article is actually quite great otherwise.