Hi,
On 2019-05-07 09:34:42 -0400, Tom Lane wrote:
> I'm inclined to wonder why bother with invals at all. The odds are
> quite good that no other backend will care (which, I imagine, is the
> reasoning behind why the original patch was designed like it was).
> A table that has a lot of concurrent write activity on it is unlikely
> to stay small enough to not have a FSM for long.
But when updating the free space for the first four blocks, we're going
to either have to do an smgrexists() to check whether somebody
concurrently created the FSM, or we might not update an existing FSM. An
inval seems much better.
Greetings,
Andres Freund