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

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

#351

Post by erikerikson »

soni96pl wrote: post #347
erikerikson wrote: post #247

Earlier quoted context omitted.

There are better approaches like pre -avoiding collisions but generating tends to be more expensive than checking.

UUID is used where checking is difficult, think distributed devices offline at a plantation. How could checking be easier in that case? It would require infrastructure that doesn't exist. There are many other cases where it's easier to handle collisions.

Agreed. While it's an uncommon scenario it is a significant case and UUID shouldn't be used in that case because as you write checking doesn't work well. Better to use an alternative such as coordinate/reserve monotonic producer IDs that get paired with monotonic, per-producer monotonic sequence IDs to produce guaranteed unique, well-ordered IDs.

[edit: in IOT it's common to issue x509 certificates as a type of authentication which could be used instead of using producer IDs. Solutions always have to be paired to use case.]

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

#352

Post by erikerikson »

tommoneytools wrote: post #348
erikerikson wrote: post #247

Earlier quoted context omitted.

There are better approaches like pre -avoiding collisions but generating tends to be more expensive than checking.

Wild edge case. Curious if they ever found the root cause.

Welcome to Hacker News.

I suspect you meant to reply to a different comment. Regardless the most plausible speculation I've read here is that the RNG used to generate the UUID is low quality.

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

#355

Post by dlcarrier »

Aurornis wrote: post #172
throwaway_19sz wrote: post #50

Funny story no one will believe, but it’s true. A good friend of mine joined a startup as CTO 10 years ago, high growth phase, maybe 200 devs… In his first week he discovered the company had a microservice for generating new UUIDs. One endpoint with its own dedicated team of 3 engineers …including a database guy (the plot thickens). Other teams were instructed to call this service every time they needed a new ‘safe’…

> One endpoint with its own dedicated team of 3 engineers > The team had its own kanban board and sprints. My early jobs were at startups startups with limited resources. Every decision to build something or hire someone was carefully made after much consideration. This story would have looked like fiction to me at the time. Later in my career I joined a startup like this where every new concern someone could think u…

I had an internship at HP that taught me to never get lost in a large conglomerate. I worked with people who's career was working on a piece of a piece of a design, only ever touching the same tiny aspect of every new project.

I can't imagine getting a job like that at a startup.

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

#356

Post by dlcarrier »

kypro wrote: post #190
Aurornis wrote: post #172

Earlier quoted context omitted.

> One endpoint with its own dedicated team of 3 engineers > The team had its own kanban board and sprints. My early jobs were at startups startups with limited resources. Every decision to build something or hire someone was carefully made after much consideration. This story would have looked like fiction to me at the time. Later in my career I joined a startup like this where every new concern someone could think u…

> My early jobs were at startups startups with limited resources. Every decision to build something or hire someone was carefully made after much consideration. This story would have looked like fiction to me at the time. This was pre-2015 > Later in my career I joined a startup like this where every new concern someone could think up turned into a new microservice with new hires to form a new team. It didn't matter…

That timeline correlates with new cell phones having fewer features than the previous generations, and was when Intel started releasing generation after generation of processor on the same fabrication process, with minimal improvement between generations.

Peak technology was 2015.

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

#357

Post by rushikesh90 »

throwaway_19sz wrote: post #50

Funny story no one will believe, but it’s true. A good friend of mine joined a startup as CTO 10 years ago, high growth phase, maybe 200 devs… In his first week he discovered the company had a microservice for generating new UUIDs. One endpoint with its own dedicated team of 3 engineers …including a database guy (the plot thickens). Other teams were instructed to call this service every time they needed a new ‘safe’…

I worked in Dell EMC when it got aquired. Most of the work was duplicated between Dell and EMC so every EMC project was stalled for further decision. In India Bangalore office situation was such that to keep jobs all used to file for patents write patents all day and they even used have patent lawyers visit office and pitch patent ideas. Patent ideas were approved and filed were sometimes using better algorithms in previous patents, like literally adding null checks.

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

#360

Post by keeganpoppen »

erikerikson wrote: post #263
keeganpoppen wrote: post #257

Earlier quoted context omitted.

exactly lmao. that is exactly what is being presented as "scalable ". sigh .

No one has yet defined the scale but almost all of the real world scenarios people are actually encountering would be handled by either of the offered solutions.

as would be a million things that don’t involve using uuids at all. it literally means nothing to say “this can be handled by centralizing your uuid store”… if you do that, you DON’T NEED UUIDS. THAT IS THE POINT!
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