On Thu, Feb 21, 2019 at 1:38 AM Tsunakawa, Takayuki <tsunakawa.ta...@jp.fujitsu.com> wrote: > Why don't we consider this just like the database cache and other DBMS's > dictionary caches? That is, > > * If you want to avoid infinite memory bloat, set the upper limit on size. > > * To find a better limit, check the hit ratio with the statistics view (based > on Horiguchi-san's original 0004 patch, although that seems modification > anyway) > > Why do people try to get away from a familiar idea... Am I missing something?
I don't understand the idea that we would add something to PostgreSQL without proving that it has value. Sure, other systems have somewhat similar systems, and they have knobs to tune them. But, first, we don't know that those other systems made all the right decisions, and second, even they are, that doesn't mean that we'll derive similar benefits in a system with a completely different code base and many other internal differences. You need to demonstrate that each and every GUC you propose to add has a real, measurable benefit in some plausible scenario. You can't just argue that other people have something kinda like this so we should have it too. Or, well, you can argue that, but if you do, then -1 from me. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company
