> To do anything with a request you are going to have a context which will function just like the stack of a thread. But a thread has a separate call stack. Re

> To do anything with a request you are going to have a context which will function just like the stack of a thread. But a thread has a separate call stack. Returning and calling another function in the same stack just involves moving the stack pointer by a few bytes. Switching to another thread’s stack will invalidate much more cache, while running an async task until await will make the best use of the existing cache, and switch (much closer in RAM than in another thread) only when it makes sense, i.e. the previous task started waiting on something. > It only matters if you are at capacity because otherwise the active requests will be cached. CPU cache is a few megabytes. That definitely won’t hold hundreds of requests if they all transfer substantial data, even if you can handle thousands or more.