10 ms·
> 48-bit pseudo-random number used as a spatially unique identifier Occupies bits 80 through 127 (octets 10-15) Is 48 bits really enough to be a spatiall
by RcouF1uZ4gsC 5y ago
> 48-bit pseudo-random number used as a spatially unique identifier
Occupies bits 80 through 127 (octets 10-15)
Is 48 bits really enough to be a spatially unique identifier. Roughly 16 million entities would have a 50% chance of collision.
If you have a spatially unique identifier collision, it seems it might be possible for two independent entities to generate the same time stamp and counter codes resulting in an overall UUID collision.
- ltbarcly3 5y agoWhile possible, with a high precision clock it should be quite rare. In any case, UUID's aren't meant to be universally unique to the point you will never see the same one for any reason across every use case in the galaxy, although many versions do allow you to neglect to code to handle collisions for almost every practical use case. If you need 16 million entries to get a 50% chance of collision, 100ns time resolution means you have 10^7 timestamps per second, so to actually experience a 50% chance of collision requires an instantaneous hash rate of over 10^14 per second, which I don't think you are likely to ever see in practice before these UUID versions are long obsolete.