Re: Autovacuum and OldestXmin

Simon Riggs wrote:
> On Thu, 2007-11-22 at 21:59 -0500, Christopher Browne wrote:

> > I imagine it might be useful to add it to autovac, too. I thought it
> > was pretty neat that this could be successfully handled by comparison
> > with a single value (e.g. - eldest xmin), and I expect that using a
> > single quasi-global value should be good enough for autovac.
>
> I've just looked at that to see if it is that easy; I don't think it is.
>
> That works for slony currently because we vacuum all of the slony tables
> at once. Autovacuum does individual tables so we'd need to store the
> individual values otherwise we might skip doing a VACUUM when it could
> have done some useful work.

Yeah, that was my conclusion too.

--
Alvaro Herrera http://www.amazon.com/gp/registry/5ZYLFMCVHXC
Voy a acabar con todos los humanos / con los humanos yo acabaré
voy a acabar con todos / con todos los humanos acabaré (Bender)