Re: BitmapHeapScan streaming read user and prelim refactoring

On Wed, Feb 12, 2025 at 3:07 PM Tomas Vondra <tomas@vondra.me> wrote:
> AFAICS the "1" value is simply one of the many "defensive" defaults in
> our sample config. It's much more likely to help than cause harm, even
> on smaller/older systems, but for many systems a higher value would be
> more appropriate. There's usually a huge initial benefit (say, going to
> 16 or 32), and then the benefits diminish fairly quickly.

I'm happy to see us change the value to something that is likely to be
good for most people. I think it's OK if people on very tiny systems
need to change a few defaults for optimum performance. We should keep
in mind that people do sometimes run PostgreSQL on fairly small VMs
and not go crazy with it, but there's no reason to pretend that the
typical database runs on a Raspberry Pi.

--
Robert Haas
EDB: http://www.enterprisedb.com