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Re:Ask HN: We just had an actual UUID v4 collision... by squirrellous on Friday May 08, 2026 @10:36PM (#48071214)
In this specific case. In the case of trace IDs (an example of which is [1]) where the equivalent of UUIDs are explicitly used to avoid coordination, it’s hard to imagine how you’d reliably detect and retry.

[1] https://news.ycombinator.com/item?id=48033853

Re:Ask HN: We just had an actual UUID v4 collision... by erikerikson on Friday May 08, 2026 @11:45PM (#48071630)
A lot of databases have a uniqueness constraint that is basically a register level compare and replace. Others have a if_not_exists which is nearly the same. If you're not targeting a serious throughput use case, it's enough. If you are then there are lots of solutions/alternatives that completely avoid coordination. On the other hand, maybe tracing protocols are robust to out of order delivery. If that won't do them sequence numbers tied to monotonic sequence IDs should be plenty. If not then I'd need very serious conversations to be convinced you're not wasting everyone's time