On Thu, 6 Apr 2023 at 13:14, David Rowley <dgrowleyml@gmail.com> wrote:
> Is it intended that VACUUM t1,t2; now share the same strategy?
> Currently, in master, we'll allocate a new strategy for t2 after
> vacuuming t1. Does this not mean we'll now leave fewer t1 pages in
> shared_buffers because the reuse of the strategy will force them out
> with t2 pages? I understand there's nothing particularly invalid
> about that, but it is a change in behaviour that the patch seems to be
> making with very little consideration as to if it's better or worse.
Actually, never mind that. I'm wrong. The same strategy is used for
both tables before and after this change.
I stumbled on thinking vacuum() was being called in a loop from
ExecVacuum() rather than it just passing all of the relations to
vacuum() and the loop being done inside vacuum(), which is does.
David