On Sun, Jun 25, 2017 at 10:33 PM, Guido van Rossum <gvanros...@gmail.com> wrote:
> On Sun, Jun 25, 2017 at 3:38 PM, Yarko Tymciurak <yark...@gmail.com> > wrote: > >> To be a well-behaved (capable of effective cooperation) task in such a >> system, you should guard against getting embroiled in potentially blocking >> I/O tasks whose latency you are not able to control (within facilities >> available in a cooperative multitasking context). The raises a couple of >> questions: to be well-behaved, simple control flow is desireable (i.e. not >> nested layers of yields, except perhaps for a pipeline case); and >> "read/write" control from memory space w/in the process (since external I/O >> is generally not for async) begs the question: what for? Eliminate >> globals, encapsulate and limit access as needed through usual programming >> methods. >> > > Before anyone takes this paragraph too seriously, there seem to be a bunch > of misunderstandings underlying this paragraph. > yes - thanks for the clarifications... I'm speaking from the perspective of an ECE, and thinking in the small-scale (embedded) of things like when in general is cooperative multitasking (very light-weight) more performant than pre-emptive... so from that space: > > - *All* blocking I/O is wrong in an async task, regardless of whether you > can control its latency. (The only safe way to do I/O is using a primitive > that works with `await`.) > > - There's nothing wrong with `yield` itself. (You shouldn't do I/O in a > generator used in an async task -- but that's just due to the general ban > on I/O.) > > - Using async tasks don't make globals more risky than regular code (in > fact they are safer here than in traditional multi-threaded code). > > - What on earth is "read/write" control from memory space w/in the process? > > -- > --Guido van Rossum (python.org/~guido) >
_______________________________________________ Async-sig mailing list Async-sig@python.org https://mail.python.org/mailman/listinfo/async-sig Code of Conduct: https://www.python.org/psf/codeofconduct/
