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The ID generation code doesn’t use hashing and has nothing to do with Facebook. The blog post was published afterwards but the sharding code predated the acquisition.

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Maybe I wasn’t clear. The integers that enter the base62 used to be autoincrements. After time they became what was published in the blog post.

If “timestamp” function is not from FB or not inspired by, then it must be a massive coincidence because FB’s IDs are almost exactly the same. They just don’t hash them with base62.

FBIDs are complicated because the number space includes legacy IDs, but the modern space have a 24-bit shard ID prefix and a 38-bit autoincrement identifier. Two of the bits are “thrown away.” Timestamps aren’t involved.

EDIT: ugh. Still early for us slackers on the West coast to do basic math.

Fair enough. They do appear to be very similar in structure and they do follow some logic in correlation to timestamp. However you seem to be more knowledgeable about it and so I will add this to my mental knowledge book.

Thank you

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