N59E25
Promises, parallel event-loops, segregated thread pools, functional fun, ...
All contents of this library are located within the namespace kaiu.
A traditional ``event-loop'' à la Win32 / Node.js.
A concurrent event-loop, consisting of multiple pools of threads.
Different pools may be used for different types of tasks, e.g. $NUMBER_OF_CPUS threads in a pool for computational tasks, lots of threads in pool for local I/O tasks, lots more threads in pool for remote I/O tasks.
This enables concurrency to be finely-tuned to balance contention on different resource groups (e.g. CPUs, network I/O, disk I/O).
Inspired by the JS q library, these promises are really just monads for representing the result of an operation.
These are basically instances of generators which generate promises then return a promise.
A promise stream produces a sequence of datum promises (of the same type), enabling asynchronous streaming of data from a producer (and then into a consumer).
After the last item has been produced, a finally result promise is produced, representing the result of the entire streaming operation.
A promise factory creates a promise, given some parameters.
It's the basic building block of an asynchronous program.
Each operation is wrapped in a promise factory, then the resulting promises can be chained to compose a more complex operation --- which can then also be published as a promise factory.
It's basically the asynchronous equivalent of a subroutine.
This is really just an asynchronous generator, using a promise stream to provide its values, then the final result promise to provide the return value of the operation.
Operator overloads are provided to create a DSL (domain-specific language) for composing asynchronous pipelines of tasks and streams from task factories and promise stream factories.
The header files are commented. Some components have their own README:
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(Promise)[https://github.com/battlesnake/kaiu/blob/master/promise.md]
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(Functional)[https://github.com/battlesnake/kaiu/blob/master/functional.md]
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(Event loop)[https://github.com/battlesnake/kaiu/blob/master/event_loop.md]
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(Task)[https://github.com/battlesnake/kaiu/blob/master/task.md]
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(Promise stream)[https://github.com/battlesnake/kaiu/blob/master/promise_stream.md]
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(Task stream)[https://github.com/battlesnake/kaiu/blob/master/task_stream.md]
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(Assertion)[https://github.com/battlesnake/kaiu/blob/master/assertion.md]
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(Tuple iteration)[https://github.com/battlesnake/kaiu/blob/master/tuple_iteration.md]
Requires g++, developed using version 5.2.0.
To build and run the tests:
make tests
To build in release-mode (optimizations enabled, warnings disabled):
make tests mode=release
To run a particular test, use the runner:
./run_test [commands]
For a description of the commands, run:
./run_test help:
For example, to build and run the promise test a leak check with valgrind:
./run_test mem: promise