Document slot's restart_lsn can go backward - Mailing list pgsql-hackers

Hackers,

While working on the patch fixing the situation when slot's
restart_lsn ends up pointing to a removed WAL segment [1], we
discovered that sometimes slot's restart_lsn can go backward
[2][3][4].  Hayato Kuroda proposed a patch [5], which improves
comments by describing this behavior.  As proposed by Amit Kapila [6],
I'm starting a new thread about this comments patch.

Any feedback on this patch?

Links.
1. https://www.postgresql.org/message-id/1d12d2-67235980-35-19a406a0%4063439497
2.
https://www.postgresql.org/message-id/OSCPR01MB1496646E4CF72B9231DB711AFF57DA%40OSCPR01MB14966.jpnprd01.prod.outlook.com
3. https://www.postgresql.org/message-id/CALDaNm1prhebmnAY_0%3D5UJ-WodSSbj6C8X-igrGa1EamtLw5BA%40mail.gmail.com
4.
https://www.postgresql.org/message-id/CALDaNm34RtDat%2BkZE_1%2BCY86pDLJM18hxNRTZx3CCGE%3DaN%3D_%3DA%40mail.gmail.com
5.
https://www.postgresql.org/message-id/OSCPR01MB1496634CF3BFEC3A491CF8111F547A%40OSCPR01MB14966.jpnprd01.prod.outlook.com
6. https://www.postgresql.org/message-id/CAA4eK1%2BqYg2nwa7TVz2xN-9FDZHLUGT7NLWHtfdeaf32KN3QEQ%40mail.gmail.com

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Regards,
Alexander Korotkov
Supabase