YACLib
C++ library for concurrent tasks execution
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Yet Another Concurrency Library
YACLib is a lightweight C++ library for concurrent and parallel task execution, that is striving to satisfy the following properties:
For more details check our design document and documentation.
For quick start just paste this code in your CMakeLists.txt
file.
For more details check install guide.
For more details about 'yaclib_std' or fault injection, check doc.
Here are short examples of using some features from YACLib, for details check documentation.
We guarantee that no more than one allocation will be made for each step of the pipeline.
We have Then/Detach
x IExecutor/previous step IExecutor/Inline
.
Also Future/Promise don't contain shared atomic counters!
You can zero cost-combine Future coroutine code with Future callbacks code. That allows using YAClib for a smooth transfer from C++17 to C++20 with coroutines.
Also Future with coroutine doesn't make additional allocation for Future, only coroutine frame allocation that is caused by compiler, and can be optimized.
And finally co_await
doesn't require allocation, so you can combine some async operation without allocation.
Same as asynchronous pipeline, but starting only after Run/ToFuture/Get. Task can be used as coroutine return type too.
Also running a Task that returns a Future doesn't make allocation. And it doesn't need synchronization, so it is even faster than asynchronous pipeline.
This is much more efficient than a mutex because
And also the implementation of strand is lock-free and efficient, without additional allocations.
First, this is the only correct mutex implementation for C++20 coroutines as far as I know (cppcoro, libunifex, folly::coro implement Unlock incorrectly, it serializes the code after Unlock)
Second, Mutex
inherits all the Strand
benefits.
This is really zero-cost, just suspend the coroutine and submit its resume to another executor, without synchronization inside the coroutine and allocations anywhere.
Doesn't make more than 3 allocations regardless of input size.
Doesn't make more than 2 allocations regardless of input size.
Sometimes it's necessary to return from one async function the result of the other. It would be possible with the wait on this result. But this would cause blocking of the thread while waiting for the task to complete.
This problem can be solved using future unwrapping: when an async function returns a Future object, instead of setting its result to the Future object, the inner Future will "replace" the outer Future. This means that the outer Future will complete when the inner Future finishes and will acquire the result of the inner Future.
It also doesn't require additional allocations.
We support Wait/WaitFor/WaitUntil
. Also all of them don't make allocation, and we have optimized the path for single Future
(used in Future::Get()
).
Effective like simple atomic counter in intrusive pointer, also doesn't require any allocation.
YACLib is a static library, that uses CMake as a build system and requires a compiler with C++17 or newer.
If the library doesn't compile on some compiler satisfying this condition, please create an issue. Pull requests with fixes are welcome!
We can also try to support older standards. If you are interested in it, check this discussion.
We test following configurations:
✅ - CI tested
👌 - manually tested
Compiler\OS | Linux | Windows | macOS | Android |
---|---|---|---|---|
GCC | ✅ 7+ | 👌 MinGW | ✅ 7+ | 👌 |
Clang | ✅ 8+ | ✅ ClangCL | ✅ 8+ | 👌 |
AppleClang | — | — | ✅ 12+ | — |
MSVC | — | ✅ 14.20+ | — | — |
MinGW works in CI early, check this.
YACLib follows the Abseil Live at Head philosophy (update to the latest commit from the main branch as often as possible).
So we recommend using the latest commit in the main branch in your projects.
This is safe because we suggest compiling YACLib from source, and each commit in main goes through dozens of test runs in various configurations. Our test coverage is 100%, to simplify, we run tests on the cartesian product of possible configurations:
os x compiler x stdlib x sanitizer x fault injection backend
However, we realize this philosophy doesn't work for every project, so we also provide Releases.
We don't believe in SemVer (check this), but we use a year.month.day[.patch]
versioning approach. I'll release a new version if you ask, or I'll decide we have important or enough changes.
We are always open for issues and pull requests. Check our good first issues.
For more details you can check the following links:
You can contact us by my email: valer.nosp@m.y.mi.nosp@m.ronow.nosp@m.@gma.nosp@m.il.co.nosp@m.m
Or join our Discord Server
YACLib is made available under MIT License. See [LICENSE](LICENSE) file for details.
We would be glad if you let us know that you're using our library.