Re: UUID v7

> On 5 Nov 2024, at 23:56, Andrey M. Borodin <x4mmm@yandex-team.ru> wrote:
>
> <v30-0001-Implement-UUID-v7.patch>

Some more thoughts on this patch version:

0. Comment mentioning nanoseconds, while we do not need to carry anything
/* Convert TimestampTz back and carry nanoseconds. */

1. There's unnecessary &3 in
uuid->data[7] = uuid->data[7] | ((uuid->data[8] >> 6) & 3);

2. Currently we store 0..999 microseconds in 10 bits, so values 1000..1023 are unused. We could use them for overflow.
Thatwould slightly increase non-overflowing capacity when generating more than million UUIDs per second on one backend.
However,given current performance of our CSPRNG I do not think this feature worth code complexity. 


Best regards, Andrey Borodin.