Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Core C++ bindings #14

Open
2 of 6 tasks
pentschev opened this issue Apr 3, 2023 · 0 comments
Open
2 of 6 tasks

Core C++ bindings #14

pentschev opened this issue Apr 3, 2023 · 0 comments

Comments

@pentschev
Copy link
Member

pentschev commented Apr 3, 2023 •
edited

I suggest we create a standalone C++ wrapper of UCX that is used by all other UCXX libraries.

This library should:

  • provide an object-oriented UCX API.
  • translate error codes to C++ Exceptions.
  • have a minimal overhead.
  • provide useful utility functions.
  • introduce C++ Futures, if we can get it to perform?
  • header-only, if not too difficult?

Authored by: @madsbk
rapids-bot bot pushed a commit that referenced this issue Dec 5, 2023
@pentschev
Use notify_one() in CallbackNotifier (#140)
197a0a9 
It is unclear why but for some reason `notify_all()` is causing futexes never to return in some situations. This occurs very frequently in CI and is also less frequently reproducible locally.

The typical stack trace for the blocked thread is shown below:

```cpp
Thread 6 (Thread 0x7f13ec84f700 (LWP 2823667) "pytest"):
#0  futex_wait (private=<optimized out>, expected=32765, futex_word=0x7ffd5186a874) at ../sysdeps/nptl/futex-internal.h:141
#1  futex_wait_simple (private=<optimized out>, expected=32765, futex_word=0x7ffd5186a874) at ../sysdeps/nptl/futex-internal.h:172
#2  __condvar_quiesce_and_switch_g1 (private=<optimized out>, g1index=<synthetic pointer>, wseq=<optimized out>, cond=0x7ffd5186a860) at pthread_cond_common.c:416
#3  __pthread_cond_broadcast (cond=0x7ffd5186a860) at pthread_cond_broadcast.c:73
#4  0x00007f140fe5f23c in ucxx::BaseDelayedSubmissionCollection<std::function<void ()> >::process() (this=0x560d0effafd0) at /repo/cpp/include/ucxx/delayed_submission.h:154
#5  0x00007f140fe5f399 in ucxx::DelayedSubmissionCollection::processPost (this=<optimized out>) at /repo/cpp/src/delayed_submission.cpp:84
#6  0x00007f140fe7ed71 in ucxx::WorkerProgressThread::progressUntilSync(std::function<bool ()>, bool const&, std::function<void (void*)>, void*, std::shared_ptr<ucxx::DelayedSubmissionCollection>) (progressFunction=..., stop=@0x560d0f6527f8: false, startCallback=..., startCallbackArg=<optimized out>, delayedSubmissionCollection=...) at /opt/conda/envs/test/x86_64-conda-linux-gnu/include/c++/11.4.0/bits/shared_ptr_base.h:1295
#7  0x00007f140fe7f3ee in std::__invoke_impl<void, void (*)(std::function<bool ()>, bool const&, std::function<void (void*)>, void*, std::shared_ptr<ucxx::DelayedSubmissionCollection>), std::function<bool ()>, std::reference_wrapper<bool>, std::function<void (void*)>, void*, std::shared_ptr<ucxx::DelayedSubmissionCollection> >(std::__invoke_other, void (*&&)(std::function<bool ()>, bool const&, std::function<void (void*)>, void*, std::shared_ptr<ucxx::DelayedSubmissionCollection>), std::function<bool ()>&&, std::reference_wrapper<bool>&&, std::function<void (void*)>&&, void*&&, std::shared_ptr<ucxx::DelayedSubmissionCollection>&&) (__f=<optimized out>, __f=<optimized out>) at /opt/conda/envs/test/x86_64-conda-linux-gnu/include/c++/11.4.0/bits/invoke.h:61
#8  std::__invoke<void (*)(std::function<bool ()>, bool const&, std::function<void (void*)>, void*, std::shared_ptr<ucxx::DelayedSubmissionCollection>), std::function<bool ()>, std::reference_wrapper<bool>, std::function<void (void*)>, void*, std::shared_ptr<ucxx::DelayedSubmissionCollection> >(void (*&&)(std::function<bool ()>, bool const&, std::function<void (void*)>, void*, std::shared_ptr<ucxx::DelayedSubmissionCollection>), std::function<bool ()>&&, std::reference_wrapper<bool>&&, std::function<void (void*)>&&, void*&&, std::shared_ptr<ucxx::DelayedSubmissionCollection>&&) (__fn=<optimized out>) at /opt/conda/envs/test/x86_64-conda-linux-gnu/include/c++/11.4.0/bits/invoke.h:96
#9  std::thread::_Invoker<std::tuple<void (*)(std::function<bool ()>, bool const&, std::function<void (void*)>, void*, std::shared_ptr<ucxx::DelayedSubmissionCollection>), std::function<bool ()>, std::reference_wrapper<bool>, std::function<void (void*)>, void*, std::shared_ptr<ucxx::DelayedSubmissionCollection> > >::_M_invoke<0ul, 1ul, 2ul, 3ul, 4ul, 5ul>(std::_Index_tuple<0ul, 1ul, 2ul, 3ul, 4ul, 5ul>) (this=<optimized out>) at /opt/conda/envs/test/x86_64-conda-linux-gnu/include/c++/11.4.0/bits/std_thread.h:259
#10 std::thread::_Invoker<std::tuple<void (*)(std::function<bool ()>, bool const&, std::function<void (void*)>, void*, std::shared_ptr<ucxx::DelayedSubmissionCollection>), std::function<bool ()>, std::reference_wrapper<bool>, std::function<void (void*)>, void*, std::shared_ptr<ucxx::DelayedSubmissionCollection> > >::operator()() (this=<optimized out>) at /opt/conda/envs/test/x86_64-conda-linux-gnu/include/c++/11.4.0/bits/std_thread.h:266
#11 std::thread::_State_impl<std::thread::_Invoker<std::tuple<void (*)(std::function<bool ()>, bool const&, std::function<void (void*)>, void*, std::shared_ptr<ucxx::DelayedSubmissionCollection>), std::function<bool ()>, std::reference_wrapper<bool>, std::function<void (void*)>, void*, std::shared_ptr<ucxx::DelayedSubmissionCollection> > > >::_M_run() (this=<optimized out>) at /opt/conda/envs/test/x86_64-conda-linux-gnu/include/c++/11.4.0/bits/std_thread.h:211
#12 0x00007f140f92fe95 in std::execute_native_thread_routine (__p=<optimized out>) at ../../../../../libstdc++-v3/src/c++11/thread.cc:104
#13 0x00007f1412647609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#14 0x00007f1412412133 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95
```

Authors:
  - Peter Andreas Entschev (https://github.com/pentschev)

Approvers:
  - Lawrence Mitchell (https://github.com/wence-)

URL: #140
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Assignees
No one assigned
Labels
None yet
Projects
None yet
Milestone
No milestone
Development

No branches or pull requests
1 participant
@pentschev