With regard to the mail, I firstly apologise for the confusion created regarding authorship. The patch was developed as part of my work in my official email id and the patch was committed under my personal GitHub account during collaborative development. Going forward, I will make sure the email address, signature, and patch author information are consistent to avoid any ambiguity in future. On reviewing your objections posted on September 25, I understood the following points :
1. Control file changes: You are correct that the control file always changes on shutdown, and that pg_rewind cannot simply ignore those updates. My earlier patch proposal did not address that, and I now understand why the server itself would reject a mismatch here.
2. Other WAL records (RUNNING_XACTS): I see now that a clean shutdown generates both RUNNING_XACTS and CHECKPOINT_SHUTDOWN. My patch only skipped over the latter, so in practice rewind would still be triggered incorrectly. I will extend the logic to also consider this sequence properly.
3. Server-side consistency: As noted, even if pg_rewind skips shutdown-only WAL records, the restarted old primary can still fail due to control file divergence (infinite loop issue). That means it needs a more holistic fix that considers both pg_rewind and server startup behavior.
4. RMID verification: I did not guard the filtering with an XLogRecGetRmid() check. I’ll fix this to avoid misclassification, following the walsummarizer.c example as you suggested.
Plan forward:
Revise the patch so that pg_rewind correctly checks RMIDs and handles both RUNNING_XACTS + CHECKPOINT_SHUTDOWN sequences, not just shutdown checkpoints.
Investigate whether control file normalization is required (or whether server-side startup logic also needs adjustments) so that an old primary can rejoin cleanly without looping.
Ensure consistent patch authorship (my name + email will match the commit and submission).
Add regression coverage under src/bin/pg_rewind/t/ to reproduce this clean-shutdown failover scenario automatically.
I’ll prepare and post a new version of the patch with these corrections. Looking forward for more suggestions from you.
Thank you for carefully reviewing and pointing out both the technical and process issues.
On Mon, Sep 29, 2025 at 6:30 AM BharatDB <bharatdbpg@gmail.com> wrote: > Dear Srinath,
This is a really weird email. First, it doesn't address my objections from September 25th. Second, the email is from BharatDB <bharatdbpg@gmail.com>, the email signature says it's from "Soumya", and the patch within is from manimurali1993 <manimurali1993@gamil.com>.
