| From: | Aleksander Alekseev <aleksander(at)tigerdata(dot)com> |
|---|---|
| To: | PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org> |
| Cc: | Jacob Brazeal <jacob(dot)brazeal(at)gmail(dot)com>, Matthias van de Meent <boekewurm+postgres(at)gmail(dot)com> |
| Subject: | Re: Write skew observed under serializable isolation |
| Date: | 2026-09-21 11:51:49 |
| Message-ID: | CAJ7c6TPjccw9zdDotmL_Fsr9MmFrp-n=A+k=rH1ANAkkjxoBCQ@mail.gmail.com |
| Views: | Whole Thread | Raw Message | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
Hi Jacob,
Thanks for the bug report and the fix.
> [...]
>
> It seems that using page locks here would require some additional notion of heap gap locking, or corresponding changes to the insert conflict checks. With the existing predicate-locking scheme, I think the relation lock is needed to cover inserts as well as updates.
Yes it looks like an architecturally correct approach with minimum
overall overhead. In any case anyone who wants to implement an
optimization can submit it as a separate patch.
My only nitpick is that the patch doesn't update README-SSI. The
corrected patch is attached. Also I added a proper commit message.
I believe the patch is Ready for Committer.
--
Best regards,
Aleksander Alekseev
| Attachment | Content-Type | Size |
|---|---|---|
| v2-0001-Fix-write-skew-under-SERIALIZABLE-for-Tid-Range-S.patch | text/x-patch | 9.8 KB |
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Aleksander Alekseev | 2026-09-21 12:01:27 | Re: Open SSI correctness issues |
| Previous Message | Nazir Bilal Yavuz | 2026-09-21 11:38:21 | Re: Stabilize and shorten test_checksums/013_rewind test |