Re: Option to not use ringbuffer in VACUUM, using it in failsafe mode

On Thu, 6 Apr 2023 at 12:42, Melanie Plageman <melanieplageman@gmail.com> wrote:
> Attached is a v12 of the whole vacuum_buffer_usage_limit patch set which
> includes a commit to fix the bug in master and a commit to move relevant
> code from vacuum() up into ExecVacuum().

I'm still playing catch up to the moving of the pre-checks from
vacuum() to ExecVacuum().  I'm now wondering...

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.

David