47 lines
1.9 KiB
Markdown
47 lines
1.9 KiB
Markdown
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Ke - Fast implementation of Queue in OCaml
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==========================================
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Queue or FIFO is one of the most famous data-structure used in several
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algorithms. `Ke` provides some implementations of it in a functionnal or
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imperative way.
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It is a little library with benchmark
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([`bechamel`](https://github.com/dinosaure/bechamel.git) or `core_bench`),
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fuzzer and tests.
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From what we know, `Ke.Rke` is the faster implementation than `Queue` from the
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standard library or the `base` package. It is limited by some kind of data (see
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[`Bigarray.kind`]()) but enough for a large amount of algorithms. The fast
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operation is to put some elements faster than a sequence of `Queue.push`, and
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get some elements faster than a sequence of `Queue.pop`.
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Then we provide a functionnal interface `Fke` or an imperative interface `Rke`.
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We extended implementations to have a limit of elements to store (see
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`Rke.Weighted` and `Fke.Weigted`). The purpose of it is to limit memory
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consumption of queue when we use it in some contexts (like _encoder_).
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Again, as a part of the MirageOS project, `Ke` does not rely on C stubs,
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`Obj.magic` and so on.
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Author: Romain Calascibetta <romain.calascibetta@gmail.com>
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Documentation: https://mirage.github.io/ke/
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Notes about Implementations
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===========================
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The functionnal implementation `Fke` is come from the Okazaki's queue
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implementation with GADT to discard impossible case.
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`Rke`, `Rke.Weighted` and `Fke.Weighted` was limited by kind and follow Xen's
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implementation of the shared memory ring-buffer. Length of the internal buffer
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is, in any case, a power of two - that means, in some context, for a large
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amount of elements, this kind of queue does not fit on your request.
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Fuzzer was made to compare the standard Queue (as an oracle) with `Rke` and
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`Fke`. We construct a set of actions (`push` and `pop`) and ensure (by GADT) to
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never `pop` an empty queue.
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