Slashdot Mirror
Facebook Goes To 64 Bit User IDs
NewsCloud writes "Facebook has announced to developers that they are moving to a 64 bit user ID in November. At 32 bits, the current ID allows nearly 4.3 billion user accounts. Yet, despite having only 47 million users today, Facebook's move to 64 bits will allow it to have more than 18 quintillion (18,446,744,074,000,000,000) user accounts. Of course, there are currently only about 6.5 billion people in the world. Is Facebook setting their sights beyond Earth or just trying to avoid what happened when Slashdot ran out of space for comment IDs last year. Perhaps they are planning to implement personas."
One thing to keep in mind is the userid is network ID + user ID for that network
For my user ID the network ID takes up the first 6 digits
Although I have heard that they stopped this practice and are just assigning IDs
My UID is prime... is yours?
The "Slashdot ran out of space for comment IDs" link doesn't work.
You can get to the referenced article at:
http://meta.slashdot.org/article.pl?sid=06/11/09/1534204
If you think you might ever have more than 2^32 of something, you kind of have to go to 2^64. Yes. It's an obscene ammount of possibilities; but it's the next biggest size. You really don't have much of a choice here. You could implement 5-byte numbers, but it'd be a PiTA. No CPUs have native 5-byte ints. The progression has always been a doubling of int size.
If that doesn't make sense, you shouldn't be on Slashdot. Maybe you should be someplace else... like Facebook maybe?
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
The difference being that the current (huge) number was not quite sufficient to register all human beings on the planet, so we have to wonder why they did this. 32-bit integers are kind of the default, so most people wouldn't worry about it. So why are they doing this?
If you look, this article is filed under "It's funny. Laugh." And it is, really. Either Facebook is doing this for no good reason, or someone actually has some justification for going to the time and expense to change their database in this way. And so... Are they really planning on registering more human beings that exist?
I realize it's not funny to you now, as you've had to have the joke explained to you...
If they suddenly went from 2 gigs of email to 5 exabytes, then yes.
Also, keep in mind that Slashdot did cover when Gmail was first released with that 2 gigs, which seemed impossibly huge, and was at least one or two orders of magnitude larger than their closest competitor.
Don't thank God, thank a doctor!
Are we going to post a news story everytime google adds to their storage system?
Answer: Why yes, I believe they will.
Not all of the bits of an ID are necessarily there for uniqueness. Wider ID's allow for features such as check digits (being able to tell whether an ID is valid without doing an existence query in a remote database) and other information. Namely, various immutable properties of the object that is denoted by the ID can be stored in the ID itself. This is similar to using spare bits within a machine address for tagging an object with a type or other attribute. It may be very useful to be able to tell something about an object just from the ID alone.