KSUID

K-Sortable Unique Identifer (KSUID) generation for Crystal. It has no external dependencies.

Installation

Add the following to your shards.yml

dependencies:
    ksuid:
        github: leoadamek/ksuid

Usage

Create a generator...

require "ksuid"

g = Ksuid::Generator.new

...and use it to create KSUIDs:

k = g.generate

Each KSUID has a total of 96-bits of data, so can be stored either as a string, or as a UInt128

Partitioning

This library supports partitioning KSUIDs, the most common use-case is to partition KSUIDs generated by different network nodes to prevent colissions in a distributed system.

Any Proc(UInt32) can be used to partition data.

The following partitioning functions are provided:

• Ksuid::Partitioner.no_partitions — Does not partition data, all KSUIDs are in partition zero.
• Ksuid::Partitioner.hostname — Partitions KSUIDs by the first 4 bytes of the system hostname. Ideal for containerized environments where hostname is guaranteed to be unique amoung active hosts.
• Ksuid::Partitioner.string(String) — Partitions KSUIDs by the first 4 bytes of any given string.

Benchmarks

All tests performed on an i7-4770S @ 3.9GHz, single thread.

Partitioning Functions

All included partitioning functions are pure, and will return the same value each time. Proc(UInt32) is used to provide the option of using impure partitioning functions if required.

          calls/s      avg.      dev.     rel speed.
    none: 458.18M (  2.18ns) (± 5.04%)  1.16× slower  
hostname: 530.06M (  1.89ns) (± 4.39%)  1.00× slower
  string: 532.38M (  1.88ns) (± 3.88%)       fastest

Encoding Functions

   to_s:   3.88M (257.94ns) (± 9.78%)  157.97× slower     
to_u128: 612.44M (  1.63ns) (± 4.56%)         fastest 

Generation

generate: 501.66k (  1.99µs) (± 3.18%)