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by sgarland 869 days ago
If the DB fails to assign an ID, it's probably broken, so having an external ID won't help you.

If you're referring to not having conflicts between distributed nodes, that's a solved problem as well – distribute chunked ranges to each node of N size.
1 comments
kiitos 869 days ago
Whatever is distributing the chunks is still a point of central coordination.
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Dylan16807 869 days ago
Yes, and?

If you can't manage minor levels of coordination because your database is on fire, the problem is that your database is on fire.

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kiitos 863 days ago
Fewer points of coordination is always better.

In general you shouldn't need to make a roundtrip to produce an ID.

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Dylan16807 862 days ago
> Fewer points of coordination is always better.

The distributed database needs a coordination system anyway, so it's not an additional point.

> In general you shouldn't need to make a roundtrip to produce an ID.

Did you forget the context over the last week? We're already talking about reserving big chunks to remove the need to make a roundtrip to produce an ID. There would instead be something like one roundtrip per million IDs.

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kiitos 857 days ago
> The distributed database needs a coordination system anyway, so it's not an additional point.

Nope! Distributed databases do not necessarily need a "coordination system" in this sense. Most wide-scale distributed databases actually cannot rely on this kind of coordination.

> Did you forget the context over the last week? We're already talking about reserving big chunks to remove the need to make a roundtrip to produce an ID. There would instead be something like one roundtrip per million IDs.

OK, it's very clear that you're speaking from a context which is a very narrow subset of distributed systems as a whole. That's fine, just please understand your experience isn't broadly representative.

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Dylan16807 855 days ago
> Nope! Distributed databases do not necessarily need a "coordination system" in this sense. Most wide-scale distributed databases actually cannot rely on this kind of coordination.

I'm assuming a system that tracks nodes and checks for quorum(s), because if you let isolated servers be authoritative then your data integrity goes to hell. If you have that system, you can use it for low-bandwidth coordinated decisions like reserving blocks of ids.

Am I wrong to think that most distributed databases have systems like that?

> OK, it's very clear that you're speaking from a context which is a very narrow subset of distributed systems as a whole. That's fine, just please understand your experience isn't broadly representative.

Sure, but the first thing you said in this conversation was "Whatever is distributing the chunks is still a point of central coordination." which is equally narrow, so I wasn't expecting you to suddenly broaden when I asked why that mattered.

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