Ühel kenal päeval, L, 2006-06-24 kell 19:36, kirjutas Bruce Momjian: > Hannu Krosing wrote: > > ?hel kenal p?eval, R, 2006-06-23 kell 13:08, kirjutas Tom Lane:
> > > > > > Bottom line: there's still lots of low-hanging fruit. Why are people > > > feeling that we need to abandon or massively complicate our basic > > > architecture to make progress? > > > > Maybe we could start from reusing the index tuples which point to > > invisible tuples ? The index is not MVCC anyway, so maybe it is easier > > to do in-place replacement there ? > > > > This probably has the same obstacles which have prevented us from > > removing those in the first place (removing instead of marking as > > invisible). Does it cause some locking issues ? Or does it go against > > some other constraints of our index lookups ? > > > > I think that just setting the invisible bit in an index leaf node causes > > nearly as much disk io as removing the node. > > > > If we could delete/reuse old index tuples, it would solve a sizable > > chunk of index-growth problem, especially for cases where referenced key > > value does not change. > > I think heap _and_ index reuse is the only useful direction. Index or > heap reuse alone seems too marginal for the added complexity. Sure, but index reuse seems a lot easier, as there is nothing additional to remember or clean out when doing it. When reusing a heap tuple you have to clean out all index entries pointing to it. -- ---------------- Hannu Krosing Database Architect Skype Technologies OÜ Akadeemia tee 21 F, Tallinn, 12618, Estonia Skype me: callto:hkrosing Get Skype for free: http://www.skype.com ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings
