Dean Rasheed <dean(dot)a(dot)rasheed(at)gmail(dot)com> writes:
> The thing I'm unsure about is whether sending sinval
> messages when the visibility map is extended is a good idea.
Seems perfectly reasonable to me. They'd occur so seldom as to be
more than repaid if we can scrape some cost out of the mainline paths.
The real objection to this probably is that if it only saves anything
for tables that don't have a VM yet, it's dubious whether it's worth
doing. But if we can avoid wasted checks for VM extension as well,
then I think it's probably a no-brainer.
regards, tom lane