python-fity3 0.7

Fity3 is a Twitter snowflake like scheme generator that fits in 53 bits.

Its scheme is:

timestamp | worker_id | sequence
 41 bits  |  8 bits   |  4 bits

Twitter’s snowflake scheme for id generation has a bunch of nice properties. An enormous number of roughly-sorted ids can be created per second in an uncoordinated manner.

However it’s painful working with 64 bit integers in environments that use IEEE 754 floating points for numerics. Particularly JavaScript and the scores for Redis’ sorted sets.

This scheme allows for:

• 69 years of ids (the same as snowflakes)

• at most 256 unique id generating workers

• each worker can produce at most 16 ids per millisecond

• so at most 4 million ids per second

If you’re building a system in the sweet spot of not being too popular that usage will grow to creating more than 4 million new things a second but you could benefit from uncoordinated incrementing id generation and don’t want to punch yourself in the face every time you request data over a websocket from JavaScript, this scheme might be a useful alternative.

>>> import fity3
>>> f3 = fity3.generator(1)
>>> next(f3)
14127739136
>>> next(f3)
14132125952
>>> next(f3)
14135079168

# convenience to convert to a unix timestamp
>>> fity3.to_timestamp(14135079168)
1413374250

Let’s just hope we won’t be the ones supporting any of these systems in 2079.