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Ask HN: We just had an actual UUID v4 collision...

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101–110 of 369 posts

Re: Ask HN: We just had an actual UUID v4 collision...

#101
post #60

According to the many-worlds interpretation of quantum mechanics, there's bound to be one branch of universe where every UUID is the same. Can you imagine what those guys are thinking?

Not only that, there's vastly more where every UUID except one is the same, but they never got to that one because they didn't ever use them.

Or where the first two are unique, but every following one is one of the first two.

Re: Ask HN: We just had an actual UUID v4 collision...

#102
post #14

The chance of a UUIDv4 collision is very low, but it is never zero. If everything is done properly, then this is very likely the one and only time anyone involved in the telling or reading of this account will ever experience this.

Classic gamblers fallacy!

Ironically one of the few comments in this thread that isn’t necessarily the gamblers fallacy!

The chance anyone involved saw or heard about the first one was near zero, now they’ve seen this one the chance they see another is still near zero (I.e unchanged).

Re: Ask HN: We just had an actual UUID v4 collision...

#104

What you're talking about is so extremely rare that it's much more likely that the entire Earth is destroyed by an asteroid right this inst...

About as rare as an asteroid typing an ellipsis and clicking the add comment button.

That’s just a result of jounce from localized gravity effects and atmospheric pressure disturbances in the moments before impact.

Think the ultrasonic typing hacking scene in Pantheon combined with the keyboard bouncing due to rumbling.

Re: Ask HN: We just had an actual UUID v4 collision...

#107

What you're talking about is so extremely rare that it's much more likely that the entire Earth is destroyed by an asteroid right this inst...

It is not quite as rare. I calculated it to be less common than being hit by a meteorite, and added a section about that and the Birthday Paradox to Wikipedia, to the article about UUIDs. It got removed / replaced a few years ago however. (If my source was correct, there was actually a woman hit by a meteorite, but she survived, with a leg injury.)

If you do have a UUID collision, chances are extremely high that it's either a software bug, or glitch in the computer. It could be a cosmic ray. Cosmic rays messing with the computer memory or CPU are actually relatively common.

Re: Ask HN: We just had an actual UUID v4 collision...

#108
post #72
post #3

1 in 4.72 × 10²⁸ 1 in 47.3 octillion. i'd be suspecting a race condition or some other naive mistake, otherwise id be stocking up on lottery tickets. (lol at the other user posting at the same time about the lottery ticket.. great minds and all that.)

The lottery ticket part makes no sense. Statistically if such an improbable event just happened to him, then chance of it happening again should be even more improbable.

No, the events are independent. If you have a UUID collide, your chance of winning the lottery if you enter it is exactly the same as it was before the UUID collision.

Re: Ask HN: We just had an actual UUID v4 collision...

#109
post #80

> I thought this is technically impossible Actually it's not impossible, but very very improbable. P.S. You should play a lottery/powerball ticket P.P.S. Whenever I use the word improbable, the https://hitchhikers.fandom.com/wiki/Infinite_Improbability_D... comes in mind

> P.S. You should play a lottery/powerball ticket Actually, they should not. That collision and winning the lottery would be even rarer.

Assuming they are independent events, OP is not more nor less likely to win the lottery now that before running in the collision. I actually have more question if you claim the events in question are NOT independent!

Re: Ask HN: We just had an actual UUID v4 collision...

#110

Most plausible cause: uuid package depends on some random number generator package, which has recently been compromised in order to make “random” numbers predictable. As a result, many crypto (ssl + currency) projects are compromised due to a supplychain attack.

Changed 3 weeks ago:

uuid/src/rng.ts : the random array is const. Every call will share the same random number. Subsequent call will update your old random code, so if you generated something important... good luck

The old code used to do a slice() which creates a new copy.

Might be unintentional. Although I have no idea how this would pass any tests, as you would think to test generating 2 randomnumbers and hope they are not the same.

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