On Thu, Mar 01, 2007 at 04:54:44PM +0200, Hannu Krosing wrote:
> > > I was not suggesting that we remove visible rows through truncation.
> >
> > Sure, unless you suggest to not truncate during this vacuum run ?
> > But we are talking about vacuum full, so truncation is essential.
> >
> > It was suggested to do a dummy null update to move live tuples up front.
> > The old version is still visible for serializable txns.
>
> There should probably be a wait-other-trxs to finish stage between
> COMPACT and 2nd VACUUM if truncation at this cycle is absolutely needed
Or you could just do a vacuum a bit later. If we've also got the DSM at
that point, vacuum should be fast.
--
Jim Nasby jim@nasby.net
EnterpriseDB http://enterprisedb.com 512.569.9461 (cell)