Greg Stark <gsstark@mit.edu> writes:
> I don't see how the lack of deletions is relevant to needing vacuum-cycle-ID.
> AFAICT there's still a risk that someone will come along and do a page split
> underneath this scan and if the page is to the left of the scan it will be
> missed.
Well, if there are active insertions or deletions happening in parallel
with the scan, the tuple count is going to be at best approximate
anyway, no? So there's no need to be tense about ensuring we visit
every single index tuple. We do want to hit all the pages so we can
clean up any recyclable pages, but that's not a problem.
regards, tom lane