Re: Can we change pg_rewind used without wal_log_hints and data_checksums

On Thu, 2026-01-15 at 14:14 +0800, lchch1990@sina.cn wrote:
> > See https://postgr.es/m/CA%2BTgmoY4j%2Bp7JY69ry8GpOSMMdZNYqU6dtiONPrcxaVG%2BSPByg%40mail.gmail.com
>
> 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. 

I apologize for my misunderstanding.

I had a brief look at the patch, and the gratuitous use of static variables didn't
appeal to me.  Can you briefly describe the algorithm?  You look at all commit
records *after* the fork, right?  Then how can you identify how far back you have
rewind?  How can you identify when a transaction started?

Yours,
Laurenz Albe