Slashdot Posting Bug Infuriates Haggard Admins 262
Last night we crossed over 16,777,216 comments in the database. The wise amongst you might note that this number is 2^24, or in MySQLese an unsigned mediumint. Unfortunately, like 5 years ago we changed our primary keys in the comment table to unsigned int (32 bits, or 4.1 billion) but neglected to change the index that handles parents. We're awesome! Fixing is a simple ALTER TABLE statement... but on a table that is 16 million rows long, our system will take 3+ hours to do it, during which time there can be no posting. So today, we're disabling threading and will enable it again later tonight. Sorry for the inconvenience. We shall flog ourselves appropriately. Update: 11/10 12:52 GMT by J : It's fixed.
Only one thing to say (Score:5, Funny)
Sorry, could not resist. (Score:2, Insightful)
Please do.
So does a first post ... (Score:5, Funny)
D'oh. (Score:5, Insightful)
And let this be a reminder to the kids - RTFM, twice!
I for one (Score:5, Funny)
Last post! (Score:5, Funny)
who we should REALLY blame (Score:5, Funny)
Thanks for breaking slashdot, jerk
Oh Noes! (Score:5, Funny)
Oops (Score:2, Funny)
Congrats taco (Score:5, Interesting)
Can anyone actually find it to see - I tried but could only get to 16777217 [slashdot.org], its likely to be in a journal or just a reply to an older article.
Re: (Score:3, Informative)
I sense a disturbance in the force (Score:5, Funny)
Better make it longer (Score:4, Funny)
So who's the killer? (Score:5, Insightful)
Re: Oh Noes! (Score:5, Funny)
I know what you mean. Y2K was supposed to put an end to civilization, but at least we'd have been able to post on slashdot.
seems strange (Score:5, Funny)
It's true that... (Score:5, Funny)
Point 2.4 of Resign Patterns: Detonator (Score:2, Informative)
Chapter 2: Destructional Patterns
2.4 Detonator
The Detonator is extremely common, but often undetected. A common
example is the calculations based on a 2 digit year field. This bomb
is out there, and waiting to explode!
Check out... (Score:3, Interesting)
Mmmm... CT, are you sure the parent index was your only problem?
2^24 (Score:5, Funny)
Comment 16,777,216 does not exist (Score:5, Informative)
Some of you are asking which comment it was that got the cid 16,777,216. The answer is that none did. For redundancy, Slashdot is now running multiple-master replication which skips values for auto-increment [mysql.com]. Our db-1 assigns odd-numbered primary key IDs, and db-2 assigns even-numbered. Right now writes are going to db-1 so newly created rows will have only odd IDs.
The comment that got 2**24-1 was this one [slashdot.org], if anyone cares :)
Sorry about the inconvenience, everyone.
Digg? (Score:5, Funny)
Wait..sorry Commodore fans. I know it had better threading than Digg.
Haggard? (Score:5, Funny)
My Reply to the Funny Comment Above This (Score:5, Insightful)
You claim that the 16,777,216th comment would have broke it but I contest that actually the 16,777,217th comment poster would be the culprit. Since it should be able to handle that many comments if it is zero referenced, and it would actually be the one after that one that would break it. You laugh but these kinds of problems plague a lot of coders?
If you don't agree with me, please respond below and reference my comment ID.
16 million posts ... (Score:5, Funny)
Holy Chit! (Score:5, Funny)
Old discussions (Score:2)
Hopefully it just rolled over, and you can add 2^24 to every value to get the parent links back.
Though I somehow doubt that will work.
Re:OMG (Score:3, Funny)
And? (Score:5, Funny)
It's a joke, kids (Score:5, Funny)
Did somebody say... (Score:5, Funny)
Sounds Familiar (Score:5, Informative)
Gay meth orgies (Score:2)
So was it fixed in Slash? (Score:5, Interesting)
Give Slashdot Subscriptions to the borkers (Score:5, Interesting)
If you can find the first guy who COULDN'T reply due to the limit, give him one too. He deserves something for his trouble.
EldavoJohn cid=16786251 reply (Score:5, Informative)
There's no telling which comment it is, because (16,777,217 + 2n) might not have been a reply, meaning it would come up correctly.
Dorks. (Score:4, Funny)
Thanks (Score:2)
(I'm not smart enough to jump into slashcode and feel at home there, so its pretty interesting to see the kinda stuff you people have to face every now and then)
Reply to 16786251 (Score:5, Informative)
``You claim that the 16,777,216th comment would have broke it but I contest that actually the 16,777,217th comment poster would be the culprit. Since it should be able to handle that many comments if it is zero referenced''
Today is the first day I've had to type subjects. (Score:4, Interesting)
I certainly admit I wasn't thinking 0-based when I wrote that. The question is, though, should we blame the person who wrote the last valid comment (therefore ruining the fun for the rest of us), or whoever wrote the first broken comment?
Also, is everyone going to add the obligatory 'parent' link on their posts today?
[ Parent [slashdot.org] ] - [ Reply to this [slashdot.org] ]
Access to the Database? (Score:5, Interesting)
16777216 (Score:2)
(http://slashdot.org/~eldavojohn/journal/ | Last Journal: Tuesday April 04, @01:06PM) Uh, this is a reply to the 8th post down from the top (remember to use this like an array and zero reference). Yes, I'm talking to you, admdrew. You claim that the 16,777,216th comment would have broke it but I contest that actually the 16,777,217th comment poster would be the culprit. Since it should be able to handle that many comments if it is zero referenced, and it would actually be the one af
May i be the first to say... (Score:5, Funny)
I always wondered where Paula Bean ended up...
RE: 16777217 GET (Score:5, Funny)
Mod parent up (Score:5, Funny)
Why are all 16 million+ comments in a single table (Score:5, Interesting)
So why, pray, is this usage pattern not accounted for in the database design?
MOD parent up! (Score:4, Funny)
I think you mean... (Score:2, Funny)
How is this possible? (Score:2)
Re:reply to comment 16786251 (Score:2)
Exactly, just link to their comment, and if you want you can even follow the standard "Re:" format if you want
This was fortold a few months ago... (Score:4, Informative)
Should have used PostgreSQL instead.. (Score:2, Insightful)
Let the flamewars begin...
Take all the time you need (Score:5, Funny)
Trolls (Score:3, Funny)
Slashed Eyeballs (Score:4, Insightful)
Open source - it's not just a buzzword, it's a way of life.
A real Slashdotter! (Score:5, Funny)
Now this is a real Slashdotter! This guy knows how to build an infinite computer!
Re: (Score:2)
Hopefully it just rolled over, and you can add 2^24 to every value to get the parent links back.
Though I somehow doubt that will work.
Or they could just use a DB backup. Does MySQL support point-in-time recovery?
Parent [slashdot.org]
Re: Old discussions (Score:2)
Hopefully it just rolled over, and you can add 2^24 to every value to get the parent links back.
Though I somehow doubt that will work.
Or they could just use a DB backup. Does MySQL support point-in-time recovery?
Parent [slashdot.org]
Misleading Title! (Score:2)
I also didn't recollect Slashdot discussing our favorite non-homosexual, non-meth-using ex-pastor recently...
24 bit? (Score:5, Insightful)
Re: Why are all 16 million+ comments in a single t (Score:5, Informative)
poot_rootbeer asks why all the comments are in one table, when the data access pattern is such that 90% of our hits are on only the most recent entries in that table.
The answer is that we used to do it this way but it's a huge pain. In 2000 we converted from having two tables for 'stories', recent and archived, and merged them together. The performance hit was not big, and it made the code so much simpler it was a no-brainer.
It's the database's job to cache properly whether we split the table or not, and the database does that just fine. The only performance problem could be when there is a rush of inserts, or updates to the same sets of rows, spanning both newer and older portions of the table, and that just doesn't happen.
If we did want to do this we wouldn't split the tables manually; the code complexity is too high a price to pay. In MySQL 5.0 we would use a MERGE [mysql.com] engine, which has issues of its own but would involve smaller changes to our code. That's still not worth it for us. What we're probably going to do is wait for MySQL 5.1 to get out of beta and then do some performance testing on tables partitioned [mysql.com] by date and see if that gains us anything. For example, a SELECT on our comments table could be limited with a WHERE clause to only retrieve rows with a date >= the discussion object's date, which for 90% of our queries MySQL 5.1 could optimize to only look at the most recent partition. If the gains turn out to be significant, then since partitioning involves very limited code changes, we'll probably do that. Generally speaking, though, database performance is not a problem for us. So far our main bottlenecks have been CPU and RAM on the webheads. As long as we don't do anything stupid our database performance has been fine, though, as today proves, we are quite capable of being stupid.
[ Parent [slashdot.org] ]
Here's... (Score:2)
Normally, accessing a non-existent comment gets you either the "nothing to see here [slashdot.org]" message or the "can't find that comment in this discussion [slashdot.org]" message. Where are the ghost comments coming from?
Re: Access to the database (Score:3, Insightful)
Not just grad students; as a DBA by profession, I'd love a crack at the DB. If nothing else, it would give me a great place to play around with MySQL. Not to mention the ability to maybe extract some interesting user-level statistics.
Of course, the odds of this happening are pretty damn low - there'd have to be an awful lot of work and review done to scrub the DB of information that is entrusted to
Just the email addresses would be a huge deal - can you imagine the market value of such a targeted list of addresses?
In short, it would be fantastically cool for them to release the DB, but it would be a lot of work on their part for no particular return. Not to mention that if they released it once, they'd no doubt be pestered to keep releasing periodic updates...then there's the bandwidth issues...and, even, the potential copyright issues (/. doesn't own the copyright on posted comments, the poster does)...then the copyright issues for stuff they do own; releasing the DB would make it trivial for a bad actor to post a mirrored slash. A little bit of domain typosquatting and some ad deals, and you could be talking about real money.
If I were them, there's no way in hell I'd even think about doing it.
But it would be cool.
Parent [slashdot.org]
Re: Arbitrary limits (Score:2)
Re: First time I had to ... something like that (Score:2)
The question is, though, should we blame the person who wrote the last valid comment (therefore ruining the fun for the rest of us), or whoever wrote the first broken comment?
The issue is that comments after 2^24 can't be replied to since their ID won't fit into the "parent" field. So the real culprit is the guy who wrote the first post that nobody could reply to.
Let the flamewars begin... (Score:5, Funny)
Let the flamewars begin...
Unthreaded flame wars are much less enjoyable.
That Explains It (Score:2)
Comment #16,777,216 should definitely get a free "Last Post" t-shirt courtesy of Slashdot and Comment #16,777,217 should definitely get a free "I
I personally... (Score:2)
...am aiming for post # 33554432 (2^25)
graphic artists (Score:5, Funny)
The number 2^24 is of interest to digital computer artists, as that is the number of unique colors combined in the commonly implemented "True Color" RGB8 space. That color space is looking pretty limiting in some respects, but that is truly a lot of unique colors when you think about it. A 16 megapixel image does not need to repeat any color used.
If all slashdot posts from the history of Slashdot were sorted into color bins,Once that were done, people could simply post their replies as a reference to existing posts. "Hey, #938D3A to you, buddy!" "Know what I think of that? #F2C2A9!"
Who needs data integrity? (Score:3, Informative)
Ah, MySQL. Where trying to insert a row with a column value larger than the column can actually store results in MySQL clipping it to the max value.
Fortunately, as of MySQL 5, you can fix this problem.
So, yes, early versions of MySQL had a brain-dead default SQL mode that simply "corrected" invalid column values, but MySQL 5 fixes this.
Now if only they would add column constraints...
Re: (Score:2)
Finally, a tale for my grandkids in the new era (Score:5, Funny)
Next, he tries Papa bear's integer, but proclaims "4 bytes is way too big for my little site, I'd just end up wasting so much."
Finally, he tries Mama bear's integer, and extols "3 bytes is just right," not noticing it was really the same as Papa Bear's bowl in disquise.
/. copyright question (Score:5, Interesting)
Regardless, while writing this post [slashdot.org] regarding why the
Comments on
If I own the copyright on the comments I've made, shouldn't I be able to rescind publication rights on them, and prevent
Or are publication rights, once granted, irrevocable?
Of course, I suppose asking questions when there's no way for people to hit reply is a specific form of vague insanity...still, I'm curious.
So how do I get to post #1? (Score:4, Informative)
Re:Old discussions (Score:3, Informative)
Whenever a post is made and it has a parent cid, that number must be stored in the table.
If MySQL saturates instead of rolling over (see this comment [slashdot.org]), then all replies after comment 16,777,215 will have the wrong parent cid, and I don't think there's any way to fix it.
hey (Score:2)
Carry on.
Bad Developers! (Score:2)
Woo, we have more data than Slashdot :) (Score:2)
... that number looks familiar ... (Score:2)
No threading? (Score:2)
4,100,000,001st Post! (Score:2)
+10 (Score:5, Insightful)
At least they didn’t try to make bullshit excuses. I respect them for being up front about the real nature of the issue.
Non-standard data types (Score:2)
In reply to an earlier thread (Score:2)
I would suggest we make a thread for just such jokes but....
weee (Score:2)
//Obscure?
I don't see anyone else using the FARK posting format, so, apparently yes.
/slashie
"flogging definition" (Score:5, Interesting)
Re: So how do I get to post #1? (Score:2)
Well, here's the oldest story I could find: posted 12/31/1997 [slashdot.org], ignoring all the stories listed as posted on 12/31/1969. But there are no comments attached, so that doesn't really help.
This [slashdot.org] is the oldest comment on the oldest story [slashdot.org] I could find that had comments, posted on 1/1/1999.
Unfortunately, it's not even close to comment #1...but it's the best I could arrange.
P [slashdot.org]
Slashdot admins and politicians (Score:2)
Anonymous Coward for president!
Use MySQL and eventually it'll bite your arse (Score:4, Informative)
I guess this is another thing to add to the MySQL gotchas page [sql-info.de]. Of course, in a decent database engine, like PostgreSQL, if you alter a column data type then the indexes are updated to reflect this.
Re: /. copyright question (Score:3, Interesting)
IMHO, probably. When you published a comment, there was no mechanism available to you, for removing comments, or even the slightest hint that one might appear in the future. You knew what you were getting into, so it could be argued that you accepted what happened.
In a more general sense, it is well-known that sending a packet to the 'Net is like opening a bottle and letting a genie out. Once you do it, it's out, and if you ever manage to shove it back inside, it'll be more a matter of luck, rather than something possible because of policy.
Re: (Score:2)
Work around (Score:2)
1. Select the post you want to reply to.
2. Click on it's CID (on the right side of the post header. Don't confuse it with the UID).
3. The post appears alone on it's own webpage.
4. Click on the reply button.
5. Now you're replying again in a tree-like fashon.
6. ???
7. Profit ! (Or infuriate the administrator who actually had a good reason to temporary force a flat style),
And here's a link [nickscipio.com] on my opinion about flat-structured forum !
Prepare to be FLOGged... (Score:2)
Let me know when you are ready, then I'll Kermit the Flog.
[insert groan here]
Re: graphic artists (Score:3, Funny)
If all slashdot posts from the history of Slashdot were sorted into color bins, ...
So, from a distance the site would blur into an ugly pastiche resembling lime green?
So why was this 24-bit to begin with? (Score:4, Insightful)
No one has quoted ObviousGuy yet? (Score:2)
mediuminty reFreshness (Score:2)
After that final Taco, you really do need a bigmint.
MOD PARENT UP!! (Score:2)
Hexplanations (Score:2)
It's nice to see a site posting reasons for breakages from time to time. I'm sick of seeing errors like "Database error, sorry for the inconvenience". Database error? Should I try again? Should I try again later? How long will it take to fix? Did someone screw up somewhere, or did some of your hardware explode?
Here, we get "Heh, we forgot to twiddle with t
Time for the AOL reply... (Score:2)