On Tue, 26 Jul 2022 at 11:02, Dilip Kumar <dilipbal...@gmail.com> wrote: > > On Tue, Jul 26, 2022 at 3:04 PM Simon Riggs > <simon.ri...@enterprisedb.com> wrote: > > > > A long time ago, Tom Lane came up with the idea that when tables get > > bloated, tables might be allowed to shrink down again in size > > naturally by altering the way FSM allocates blocks. That's a very good > > idea, but we didn't implement it back then... > > > > This patch allows the Heap to specify what FreeSpaceStrategy it would > > like to see.
> I think this is a really interesting idea. So IIUC this patch enables > an option to select between the strategy but don't yet decide on that. Correct > > All we need is a simple heuristic to allow us to choose between > > various strategies. > > I think it would be really interesting to see what would be the exact > deciding point between these strategies. Because when we switch from > CONCURRENCY to COMPACT it would immediately affect the insert/update > performance but it would control the bloat. So I am not sure whether > the selection should be completely based on the heuristic or there > should be some GUC parameter where the user can decide at what point > we should switch to the COMPACT strategy or it should not at all > switch? How and when is the right question. I am happy to hear thoughts and opinions from others before coming up with a specific scheme to do that. -- Simon Riggs http://www.EnterpriseDB.com/
