Alvaro Herrera <alvherre@commandprompt.com> writes:
> I think there is a reasonable case for saying that a manual vacuum could
> hint pgstat to create the entry instead.
The problem with that is that a simple "VACUUM;" would force pgstat to
populate its entire hashtable. Which more or less defeats the idea of
not wasting table space on inactive tables --- and given the way the
reporting-file mechanism works, there's definitely an incentive to not
make the table bigger than it has to be.
It wouldn't be so bad if pgstat had a mechanism for aging out unused
table entries ...
regards, tom lane