Yongkee, > Thank you for the references. I will take a look at the benchmarks and the > publications. Hartmut's talks at CppCon brought me to HPX and I'm just > done with watching HPX tutorials in CSCS by Thomas and John. I do also > thank you for great lectures and tutorials about HPX. > > While I will be trying to learn more from the benchmarks and publications, > let me ask a bit more specific questions. First of all, is a coroutine > implemented in HPX is just about same as C++ coroutine discussed in TS, > which is stackless and relies solely on a compiler for transformations and > optimizations, or is there anything more in HPX than that?
HPX can do both, stack-full and stack-less coroutines. The main HPX scheduler relies on stack-full coroutine, those however are not directly visible to the user. Those are disguised as HPX threads. You can build stackl-ess coroutines in your code on top of that regardless. We have tried to adapt co_await to our stack-full coroutines. > Also, could any of you point out if there is any example with coroutines > and active messages? I found a few with await but unfortunately > fibonacci_await failed, as commented in CMakeList, with an > exception( what(): abandoning not ready shared state: HPX(broken_promise) > ). I also found transpose_await but haven't had a chance to run it. Ok, thanks for letting us know. The co_await support in HPX is experimental at best and was tested (if at all) with MSVC only. And, it was a while back, so the spec might have changed and our implementation is not correct for compilers today anymore. What compiler do you use? > More examples are always better so please let me know if there is any > more example for coroutines and active message. As said, HPX does not directly expose coroutines, it uses a (stackfull) coroutine-like mechanism for scheduling its lightweight threads. Everything in HPX relies on essentially two scheduling functions: Fire&forget: create a new thread and continue: hpx::apply([exec, ]f, args...); Create a new thread getting future back for extracting the result: hpx::future<T> f = hpx::async([exec, ], f, args...); // ... T result = f.get(); Our co_await implementation wraps our hpx::future's hpx::future<T> f = hpx::async([exec, ], f, args...); // ... T result = co_await(f); Active messages enter the picture if either the apply or the async above target a remote object. HTH Regards Hartmut --------------- http://stellar.cct.lsu.edu https://github.com/STEllAR-GROUP/hpx > > Thanks, > Yongkee > > On Mon, Jan 28, 2019 at 12:26 AM Thomas Heller > <mailto:thom.hel...@gmail.com> wrote: > Hi Yongkee, > > In addition to the performance tests, we published a wide range of > papers looking at the performance. Pleas have a look here: > http://stellar-group.org/publications/ > > On Sun, Jan 27, 2019 at 6:16 PM Hartmut Kaiser > <mailto:hartmut.kai...@gmail.com> wrote: > > > > Hey Yongkee, > > > > Thanks for your interest in HPX! > > > > > While I was looking for programming model and runtime system which > support > > > both active messages and coroutines, I get to know HPX and now I am > trying > > > to learn it with nice tutorials. > > > > > > I haven't (and can't) decided yet whether I am going for HPX for my > > > research yet since I am not so sure if HPX is competitive in terms of > its > > > runtime performance (or overhead) as compared to others, if any. > > > > > > For example, I am wondering what differences are between HPX > coroutines > > > and LLVM implementation with libc++, which is also getting to pretty a > > > stable stage I believe. For active messages I am not much aware of > others > > > but I remember UPC or UPC++ is designed as PGAS language. > > > > > > HPX is still the best candidate for my research because it supports > all > > > fun features within the single framework. But before going further, it > > > would be great for me to see any study about how much the runtime > system > > > is comparatively lightweight and scalable especially in terms of both > > > features: active messages and coroutines. > > > > > > Please let me know if there is any prior study for me. Also any > comment > > > with regard to my concerns above would be greatly appreciated! > > > > We have a couple of benchmarks here: > > https://github.com/STEllAR- > GROUP/hpx/tree/master/tests/performance/local. > > That's where you might be interested in starting your investigations. > > > > HTH > > Regards Hartmut > > --------------- > > http://stellar.cct.lsu.edu > > https://github.com/STEllAR-GROUP/hpx > > > > > > > > > > _______________________________________________ > > hpx-users mailing list > > mailto:hpx-users@stellar.cct.lsu.edu > > https://mail.cct.lsu.edu/mailman/listinfo/hpx-users > _______________________________________________ > hpx-users mailing list > mailto:hpx-users@stellar.cct.lsu.edu > https://mail.cct.lsu.edu/mailman/listinfo/hpx-users _______________________________________________ hpx-users mailing list hpx-users@stellar.cct.lsu.edu https://mail.cct.lsu.edu/mailman/listinfo/hpx-users
