The one problem with this "perfectly" sequential UUIDs is that it can easily lead to index bloat. Imagine you have such sequential UUIDs generated over a year,

The one problem with this "perfectly" sequential UUIDs is that it can easily lead to index bloat. Imagine you have such sequential UUIDs generated over a year, for example. And then you delete e.g. 99% of old data (say, everything except some records that you're required to keep for audit purposes or whatever). If there was an index, the "old" part will be 99% empty. For regular UUIDs this would be fine, because new entries would get routed to this part of the index and the space would be reused. Not so for sequential UUIDs (v7/v8). This is mostly why year ago I wrote "sequential-uuids" extension, doing roughly what v7/v8 do, but wrapping the timestamp once in a while. Of course, if you don't delete data, this is not an issue and v7/v8 will work fine.