Re: Can we change pg_rewind used without wal_log_hints and data_checksums

On Thu, 2026-01-15 at 13:47 +0800, laurenz.albe@cybertec.at wrote:
> Now if we run pg_rewind on server A, it examines the local WAL to find all the blocks
> that were modified after the last common checkpoint (which happened in step 3 above).
> If neither wal_log_hints = on nor checksums are enabled (which effectively forces
> WAL-logging hint bit changes), there is no track of step 5 in the WAL, and pg_rewind
> fails to copy that block from server B.  The consequence is that after pg_rewind, the
> row is *still* visible on server A because of the hint bits.  That is data corruption.
> Therefore, the requirement cannot be relaxed.


Yes I known the step and I have check the mail link. As described in the top mail we can
find some way to solve the problem so that pg_rewind can run without wal_log_hints and
data_checksums.

Currently pg_rewind search wal start at checkpoint lsn or redo lsn, I mean to search more
wal to cover whole releated transactions so any releated pages with copyed, and we never
warried about hint bits issue.

Anyway, I wish this mail in order.



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Best Regards,

Movead Li