Bruce Momjian <bruce@momjian.us> writes:
> So, can't this be improved to allow more aggressive vacuuming?
Not at that level. We do not keep track of the oldest still-used
snapshot in a transaction. I'm dubious that it'd be worth the
bookkeeping trouble to try --- often as not, the problem with a
"long running transaction" is that it's a long running statement,
anyway.
regards, tom lane