Re: Emit fewer vacuum records by reaping removable tuples during pruning - Mailing list pgsql-hackers

On Fri, Jan 5, 2024 at 1:47 PM Robert Haas <robertmhaas@gmail.com> wrote:
>
> On Fri, Jan 5, 2024 at 12:59 PM Melanie Plageman
> <melanieplageman@gmail.com> wrote:
> MP> I am planning to add a VM update into the freeze record, at which point
> MP> I will move the VM update code into lazy_scan_prune(). This will then
> MP> allow us to consolidate the freespace map update code for the prune and
> MP> noprune cases and make lazy_scan_heap() short and sweet.
>
> Can we see what that looks like on top of this change?

Yes, attached is a patch set which does this. My previous patchset
already reduced the number of places we unlock the buffer and update
the freespace map in lazy_scan_heap(). This patchset combines the
lazy_scan_prune() and lazy_scan_noprune() FSM update cases. I also
have a version which moves the freespace map updates into
lazy_scan_prune() and lazy_scan_noprune() -- eliminating all of these
from lazy_scan_heap(). This is arguably more clear. But Andres
mentioned he wanted fewer places unlocking the buffer and updating the
FSM.

- Melanie