On 25 June 2013 00:51, Bruce Momjian <br...@momjian.us> wrote: > On Sat, Jun 15, 2013 at 11:39:23AM -0400, Tom Lane wrote: > > Simon Riggs <si...@2ndquadrant.com> writes: > > > On 15 June 2013 00:01, Josh Berkus <j...@agliodbs.com> wrote: > > >> If we're going to start adding reloptions for specific table behavior, > > >> I'd rather think of all of the optimizations we might have for a > > >> prospective "append-only table" and bundle those, rather than tying it > > >> to whether a certain index exists or not. > > > > > I agree that the FSM behaviour shouldn't be linked to index existence. > > > IMHO that should be a separate table parameter, WITH (fsm_mode = > append) > > > Index only scans would also benefit from that. > > > > -1 ... I cannot believe that such a parameter would ever get turned on > > in production by anyone. If your table has a significant update rate, > > the resulting table bloat would make such behavior completely > > infeasible. If you have few enough updates to make such a behavior > > practical, then you can live with the expensive index updates instead. > > Can you have pages that are receiving updates _not_ track min/max, until > the page is nearly full? This would require full scans of such pages, > but there might be few of them. The amount of free spaces on the page > as reported by FSM might be useful here. >
Yes, that is the proposal. Just like index only scans. -- Simon Riggs http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services
