On Tue, Feb 17, 2026 at 8:11 PM Peter Geoghegan <pg@bowt.ie> wrote:
> FWIW, the version of the patch you're using is slightly different to
> the one I have here. Since I worked on unrelated issues with things
> like the cost of rescans with nestloop joins. Another difference is
> that the memory allocation for the VM cache is now combined with the
> main batch alloc, which seems to be more cache efficient. And saves us
> memory for plain index scans.
Here's a rebased branch with all of those mostly-unrelated optimization:
https://github.com/petergeoghegan/postgres/tree/index-prefetch-master-vmcache-rescan-optimizations
I suggest that you work off of this, on the off chance that these new
optimizations end up mattering. Which is quite possible with anything
that involves an index-only scan.
--
Peter Geoghegan
