Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:
> No spinlock. I was going to just grab a snapshot as it existed. If it
> changes while I am grabbing it, I just try again.
Unless, of course, you follow a now-dangling pointer and cause a backend
crash. But even without that, how do you know whether you grabbed a
self-consistent snapshot or not?
regards, tom lane