Generates a Snowflake ID. This implementation is slightly different than the original snowflake ID but still maintains its most important characteristics: 64-bit integer, unique ID generation within a distributed cluster, and timestamp sortable.

To generate a flake ID, you must explicitly "start" the system. This is separate from the typical BEAM application startup. The flake application needs to know what the assigned machine ID is, as well as how many worker processes to create. You can't create more than 64 workers.

Flake.start(0, 20) # assigns a machine id of 0 and creates 20 worker processes
Flake.start(0)     # assigns a machine id of 0 and defaults to the number of System.schedulers()

After starting up, you can generate a flake ID with:

{:ok, flake} = Flake.get_id(20)

As a performance optimization, you must explicitly request which worker to generate an id. If you started with 20 worker processes, then the valid range is 1 - 20, inclusive. For troubleshooting or general testing, you can get a breakdown of the flake components as a map:

# returns %{time: timestamp, machine_id: machine_id, worker_id: worker_id, counter: counter}
components =
    Flake.get_id(20)
    |> Flake.get_flake_components()

The package can be installed by adding flake to your list of dependencies in mix.exs:

def deps do
  [
    {:flake, "~> 0.1.0"}
  ]
end

Flake ID's are 64-bit, unsigned integers broken down into four separate components:

Performance testing was performed on an Apple M3 Pro, 18GB memory, 11 cores.

Used the following script for testing:

workers = 20
work = div(1_000_000, workers)
Flake.start(1, workers)

{time, ids} =
  :timer.tc(fn ->
    ts =
      for j <- 0..(workers - 1),
          do:
            Task.async(fn ->
              for _i <- 1..work do
                {:ok, id} = Flake.get_id(j)
                id
              end
            end)

    for t <- ts, do: Task.await(t)
  end)

The test consistently yields a result of 0.59 seconds per 1,000,000 ID's, about 1.6 - 1.7 million per second. Theoretically, since no consensus is involved in generating an ID, adding servers would multiply this result. More results will be posted in the future.