7 ms·
Twitter's UID associated to each tweet will very soon exceed 2,147,483,647
- cl3m 17y agoMore at http://blog.programmableweb.com/2009/06/09/the-twitpocalypse-is-near-will-your-twitter-client-survive/ http://blog.programmableweb.com/2009/06/09/the-twitpocalypse...
- sho 17y agoThat is quite an amazingly high number. Surely 100m people have not posted 2,000 "tweets" each. I wonder what proportion of the total is human-typed, and how much is machine generated?
- axod 17y agoAmazingly high? considering how long twitter has been going? It's extremely small IMHO. http://news.ycombinator.com/item?id=648725 http://news.ycombinator.com/item?id=648725 "Just 10% of Twitter users generate more than 90% of the content, a Harvard study of 300,000 users found." I'd expect most of it is machine generated.
- hugothefrog 17y agoI'd also expect most of those numbers not to be used. Their db writes are probably not contending on one monotonic counter. They're probably using some numbering scheme which guarantees uniqueness across multiple writable databases, but not global serialisation based on id.
- bretthoerner 17y agoI'm not sure how they'd be doing that and still giving each tweet a number so close to all the others. I have no idea where you see a "public timeline" as people mentioned above, so I just did a search for "i"... the following tweets were about a second apart. 2088840357 2088840362 (difference of 5, and that's without a real public timeline where you could easily prove each tweet takes the next number in a sequence) So it isn't as if they're using UUIDs or something unique... they very much seem to be relying on a single counter (currently).
- hugothefrog 17y agoFor a first guess, if there were 5 writing dbs, each could write every 5th id, starting at a different index (0,1,2,3,4). You'd end up with globally unique ids, and as long as your writes were (approx.) evenly distributed, all 5 sequences would be (approx.) close to each other. Who knows, they might have 100 writable dbs, with only 70% up at any point in time, meaning only 70% of all integers are actually used.. anyway, I don't know, I can just imagine them doing something like this if they wanted certain things from the system.
- hboon 17y agoNo. Because their API exposes an explicit ordering of the IDs - there is a sinceID: parameter.
- Timothee 17y agoYou can get the public timeline from here: http://twitter.com/public_timeline http://twitter.com/public_timeline Note that one can delete a message, which could explain some gaps.
- jackowayed 17y agoI think the gaps are mostly people posting protected tweets, which thus don't get into the public timeline.
- jonknee 17y agoThey do something like that with userid's. Used to be incrementing and now they have gaps.
- cperciva 17y agoSurely 100m people have not posted 2,000 "tweets" each. Two billion tweets would be 1M people posting 2k tweets each, or 100M people posting 20 tweets each.
- sho 17y agoOh. Oops. Of course you are right. That was pretty dumb of me : /
- pierrefar 17y agoIt's actually sooner. They assume 83 tweets per second (reference 2) but the number is 200 tweets per second: http://friendfeed.com/scobleizer/50e673d8/some-stats-from-twitter-conference-compared-to http://friendfeed.com/scobleizer/50e673d8/some-stats-from-tw...
- m_eiman 17y agoFrom the link: "Twitter is seeing about 200 tweets per second, during peak loads. - Robert Scoble" Note "during peak loads", so 83 is probably not too far off.
- jsdalton 17y agoThey must read HN. It now says: 2 at a rate of 151 tweets per seconds
- IsaacL 17y ago"Values updated every 5 minutes". Looking at the source (I don't actually know JavaScript, but it seems pretty simple) I'm assuming that means they get the current TwitID AND the current rate of increase.
- DrJokepu 17y agoIn the age of multicore 64 bit CPUs, they're not using signed 32 bit integers as primary key, do they?
- domdefelice 17y agoI think the problem is not in twitter itself but in the services using their APIs.
- thristian 17y agoTo be fair, they say "For some of your favorite third-party Twitter services not designed to handle such a case..." rather than accusing Twitter themselves of primary-key ineptitude.
- ks 17y agoTwitter is using an unsigned 64-bit bigint according to this: http://twitter.com/twitterapi/status/2048659057 http://twitter.com/twitterapi/status/2048659057
- Steve0 17y agoMeh, anyone who's coding for this platform must have put those id's in a unsigned integer, wouldn't they?
- tjogin 17y agoIt's such a low barrier of entry and almost non-existant learning curve to code for Twitter, so I expect quite a lot of services to have made that mistake. Not the big ones, though.
- patio11 17y agoI suspect for a lot of people coding against Twitter the notion of integers being signed or unsigned is about as foreign to their experience as pointer arithmetic. I do not consider that a bad thing. irb > "2,147,483,647".gsub(",","").to_i + 1 2147483648 (Forgive the extra code necessary to strip out the commas. The Windows irb console leaves a little to be desired in terms of midline editing.)
- there 17y agoyou know ruby supports _ as a comma separator, right? irb(main):002:0> 2_147_483_647 + 1 => 2147483648
- TweedHeads 17y agoALTER TABLE twits MODIFY COLUMN twitid BIGINT UNSIGNED NOT NULL There, fixed, send check for $20 to donations@redcross.org Call me back when they reach 18446744073709551615
- sanj 17y agoAssuming that Rails is still interacting with the DB, and the ID in question is the primary key (ie, the 'id' on the 'twits' table) isn't quite that easy. I had to do this a couple of years back when I realized I had a table that'd grow quickly: http://snippets.dzone.com/posts/show/4422 http://snippets.dzone.com/posts/show/4422 Feel free to send the donation to the same place.
- fleaflicker 17y agoThat command will take several hours to complete and write lock the table.
- TweedHeads 17y agoNothing the fail whale can't fix ;-)
- jsonscripter 17y agoWhy can't you just redirect the writes to a new temporary table and join the original and temporary on reads? (I'm not a database admin)
- lallysingh 17y agoAnyone notice the footnote on the estimated time of crossing? "3 the average tweets per second and the Twitpocalypse date are a rough approximation, please do not schedule any vacation around that date"
- ivankirigin 17y agoMaybe I'm just paranoid, but I index the tweet id's in Tipjoy with a string: tweetId = models.CharField(max_length=50, db_index=True)
- dpcan 17y agoI figure many twitter apps are written with SQLite as their database (in AIR, etc) so the Integer, Primary Key, can get up to 9223372036854775807 http://www.sqlite.org/faq.html http://www.sqlite.org/faq.html What is the point of creating a website like this?
- drawkbox 17y agoAlways use a UUID or GUID (same thing) in todays web applications. When we get to terrabytes of data as the norm for apps int based keys are going to seem so ancient. Sure it takes more room but space it cheap, and it makes syncing and distributed databases so much easier (not tied to one machine or cluster)
- charlesju 17y agoI'm going to put money down that this will not affect anything.