Re: relfrozenxid may disagree with row XIDs after 1ccc1e05ae

Bowen Shi <zxwsbg12138@gmail.com>

From: Bowen Shi <zxwsbg12138@gmail.com>

To: Melanie Plageman <melanieplageman@gmail.com>

Cc: Robert Haas <robertmhaas@gmail.com>, Matthias van de Meent <boekewurm+postgres@gmail.com>, Noah Misch <noah@leadboat.com>, Peter Geoghegan <pg@bowt.ie>, Alexander Lakhin <exclusion@gmail.com>, PostgreSQL mailing lists <pgsql-bugs@lists.postgresql.org>, Andres Freund <andres@anarazel.de>

Date: 2024-05-15T02:43:32Z

Lists: pgsql-bugs

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Ensure vacuum removes all visibly dead tuples older than OldestXmin
- 06bf404cd07b 16.4 landed
- 45ce054c02b8 14.13 landed
- dc6354c67017 15.8 landed
Combine freezing and pruning steps in VACUUM
- 6dbb490261a6 17.0 cited
Handle non-chain tuples outside of heap_prune_chain()
- 6f47f6883151 17.0 cited
Fix false reports in pg_visibility
- e85662df44ff 17.0 cited
Remove retry loop in heap_page_prune().
- 1ccc1e05ae8f 17.0 cited
vacuumlazy.c: document vistest and OldestXmin.
- 73f6ec3d3c8d 15.0 cited
Deduplicate choice of horizon for a relation procarray.c.
- d9d8aa9bb9aa 15.0 cited
Remove tupgone special case from vacuumlazy.c.
- 8523492d4e34 14.0 cited
Simplify state managed by VACUUM.
- b4af70cb2103 14.0 cited
Recycle nbtree pages deleted during same VACUUM.
- 9dd963ae2534 14.0 cited
snapshot scalability: Don't compute global horizons while building snapshots.
- dc7420c2c927 14.0 cited
Raise error when affecting tuple moved into different partition.
- f16241bef7cc 11.0 cited

> On Wed, May 15, 2024 at 7:33 AM Melanie Plageman <
> melanieplageman@gmail.com> wrote:

> Are you reproducing the hang locally with my repro? Or do you have
> your own repro? How are you testing pg_terminate_backend() and seeing
> that the InterruptHoldoffCount is 1?
>

I noticed this problem occurring several times on PG16, but I didn't use
your repro, and haven't found a way to reproduce the problem. Instead, I
simply force the vacuum to enter a retry loop with the following code and
found InterruptHoldoffCount is 1.

// if (unlikely(res == HEAPTUPLE_DEAD))
    goto retry;

Sorry, I should have mentioned that patch was against REL_14_STABLE.
> Attached patch has the same functionality but should apply cleanly
> against REL_15_STABLE.
>

Thanks, I would try that.

-- 
Regards
Bowen Shi