uuix

A tiny (<1KB) and fast UUID (v4) generator for Crystal

This is the Crystal version of @lukeed/uuid

Installation

1. Add the dependency to your shard.yml:

   dependencies:
     uuix:
       github: krthr/uuix

2. Run shards install

Usage

require "uuix"

puts UUIX.random # bc524cd7-5ec3-48c4-9bcc-e9013c69dd6e

Benchmarks

Actual version:

Using String.build (to optimize string generation). Proposed by Sergey Kuznetsov in this thread

Crystal 1.1.1 [6d9a1d583] (2021-07-26)

LLVM: 10.0.1
Default target: x86_64-unknown-linux-gnu
        UUIX:   2.71M (368.51ns) (± 9.29%)  321B/op        fastest
Crystal UUID:   1.15M (867.45ns) (± 3.78%)  0.0B/op   2.35× slower

Original version:

Crystal 0.33.0 [612825a53] (2020-02-14)

LLVM: 8.0.0
Default target: x86_64-unknown-linux-gnu
        UUIX: 920.14k (  1.09µs) (± 9.68%)  880B/op        fastest
Crystal UUID: 647.32k (  1.54µs) (± 7.53%)  0.0B/op   1.42× slower

Performance

Taken from https://github.com/lukeed/uuid

The reason why this UUID.V4 implementation is so much faster is two-fold:

1. It composes an output with hexadecimal pairs (from a cached dictionary) instead of single characters.
2. It allocates a larger Buffer/ArrayBuffer up front (expensive) and slices off chunks as needed (cheap).

The internal ArrayBuffer is 4096 bytes, which supplies 256 random invocations.

A larger buffer would result in higher performance over time, but I found this to be a good balance of performance and memory space.

Contributing

1. Fork it (https://github.com/krthr/uuix/fork)
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

Contributors

• krthr - creator and maintainer