Considering replacing ETS usage. Ideas here (please share yours, too)

[ryanwinchester]

Share ideas on how to replace the ETS table.

Requirements:

1. We need to be able to atomically increment a randomly-seeded 18-bit counter.
2. Reset+reseed every time we have a different millisecond timestamp.
3. Reset it to next millisecond at rollover.
4. Not have it grow infinitely.

Arguments:

1. current millisecond timestamp and
2. a 17-bit random integer for a seed.

Current implementation:

We have an ETS table that has timestamps as the key, and updates a counter.

  defp update_counter(timestamp, seed) do
    :ets.update_counter(__MODULE__, timestamp, 1, {timestamp, seed})
  end

Once it hits the 18-bit threshold we then increment the millisecond timestamp key to avoid rollover.

We also delete old keys on a recurring interval.

[ryanwinchester]

Current idea I want to explore is to use a NIF.

NIF ideas to explore

• consider https://github.com/xacrimon/dashmap
• [TODO: add more here. any other ideas?]