Alvaro Herrera <[EMAIL PROTECTED]> writes:
> Tom Lane wrote:
>> Uh, why?

> Because it's used to determine the Xmin that our vacuum will use.  If
> there is a transaction whose Xmin calculation included the Xid of a
> transaction running vacuum, we have gained nothing from directly
> excluding said vacuum's Xid, because it will affect us anyway indirectly
> via that transaction's Xmin.

But the patch changes things so that *everyone* excludes the vacuum from
their xmin.  Or at least I thought that was the plan.

                        regards, tom lane

---------------------------(end of broadcast)---------------------------
TIP 6: explain analyze is your friend

Reply via email to