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Facebook Goes To 64 Bit User IDs

Posted by ryuzaki0 on from the internet-users-on-mars-or-europa-can-expect-to-sign-up-soon dept.

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."

2 of 144 comments (clear)

  1. News? by JRGhaddar · · Score: 5, Insightful

    This has to one of the dumbest articles to reach the slashdot headlines.

    So basically facebook changed there maximum users from a huge number to an even bigger number.

    Are we going to post a news story everytime google adds to their storage system?
    or microsoft adds another bloated line of code?
    or everytime the telco's build a tower?

  2. I can see a few reasons by Jay+L · · Score: 5, Insightful

    Even it if it's just user IDs, and not object IDs as another user posted...

    * 64-bit user IDs are easier to partition. They could be using the top N bits as a database ID.

    * They may want to allocate the IDs randomly instead of sequentially. 64-bit IDs would involve fewer collisions.

    * We don't know what their account churn rate is; if people sign up, forget, and create new accounts again frequently, they could have many more than 47 million dormant accounts sitting around.

    A 32-bit ID really does get cramped when you have a large user base.