Re: Periodic FSM vacuum doesn't happen in one-pass strategy vacuum.

On Mon, Jun 30, 2025 at 10:20 PM Melanie Plageman
<melanieplageman(at)gmail(dot)com> wrote:
>
> On Tue, Jun 24, 2025 at 6:59 PM Melanie Plageman
> <melanieplageman(at)gmail(dot)com> wrote:
> >
> > So, I think we should commit the fix you proposed.

I agree with your analysis.

> >
> > The only question I have left is implementation: should we have
> > ndeleted as an output parameter of lazy_scan_prune() or have
> > lazy_scan_prune() return it (instead of void)?
> >
> > In <= 16, heap_page_prune() returned the number of tuples deleted, so
> > I thought of maybe having lazy_scan_prune() do this. Though, maybe it
> > is confusing to have one result returned as the return value and the
> > others returned in output parameters unless there is something more
> > special about ndeleted. With heap_page_prune(), I think it was the
> > return value because that was kind of what heap_page_prune()
> > "accomplished".

Given your comment, I now think it makes sense to have
lazy_scan_prune() return the number of deleted tuples as one of the
main jobs of this function is to delete tuples by HOT pruning. I've
updated the patch accordingly.

> Just checking what you thought about this. We probably want to get
> this committed and backported relatively soon. I'm happy to help with
> that if needed but just want to make sure we are on the same page
> about the fix.

I've attached the updated patches for master and backbranches (v17 and
v18). Please review these patches.

Regards,

--
Masahiko Sawada
Amazon Web Services: https://aws.amazon.com