| From: | shihao zhong <zhong950419(at)gmail(dot)com> |
|---|---|
| To: | Nazir Bilal Yavuz <byavuz81(at)gmail(dot)com> |
| Cc: | Bertrand Drouvot <bertranddrouvot(dot)pg(at)gmail(dot)com>, pgsql-hackers(at)lists(dot)postgresql(dot)org, Melanie Plageman <melanieplageman(at)gmail(dot)com>, Thomas Munro <thomas(dot)munro(at)gmail(dot)com> |
| Subject: | Re: Fix ReadStream handling when heap rescan strategy changes |
| Date: | 2026-11-04 03:32:25 |
| Message-ID: | CAGRkXqSX6PzrydJ6OeOOiYC+GKT_uhmivG+AB3uO+emTubv8wA@mail.gmail.com |
| Views: | Whole Thread | Raw Message | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
Hi Bertrand,
I am not sure the dangling pointer case can happen on master today.
initscan() only frees the strategy if SO_ALLOW_STRAT gets cleared or
the table drops below NBuffers / 4. The only caller of
table_rescan_set_params() is SampleScan, and a sample scan has no read
stream on master.
I don't think the table can shrink either, because truncation takes an AE
today.
This is something I really hope we can get fixed/improved.
Back to the main topic, I think on master the worst case scenario is the
one in your 0002, which causes more buffer pollution.
Thanks,
Shihao
| From | Date | Subject | |
|---|---|---|---|
| Next Message | shveta malik | 2026-11-04 03:33:13 | Re: BUG? Unpublished generated columns are reported "missing" by the subscription |
| Previous Message | Henson Choi | 2026-11-04 03:10:35 | Re: Row pattern recognition |