On Tue, Apr 14, 2015 at 6:22 PM, Peter Geoghegan <p...@heroku.com> wrote: > Why is that good?
We did discuss this before. I've recapped some of what I believe to be the most salient points below. > I think that people were all too quick to dismiss the idea of a wall > time interval playing some role here (at least as a defense against > correlated references, as a correlated reference period). I suppose > that that's because it doesn't fit with an intuition that says that > that kind of interval ought to be derived algebraically - magic delay > settings are considered suspect. Yep, Tom gave that reason here: http://www.postgresql.org/message-id/11258.1397673...@sss.pgh.pa.us But there was also this point from Andres - gettimeofday is not free: http://www.postgresql.org/message-id/20140416075307.gc3...@awork2.anarazel.de And this point from me - this can degrade to random eviction under high pressure: http://www.postgresql.org/message-id/ca+tgmoayuxr55zueapp6d2xbyicjwacc9myyn5at4tindsj...@mail.gmail.com You'll notice that my proposal avoids all three of those objections. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
