Interresting. My DB is not heavily loaded yet so I don't see any problem at this time. I just follow recommendations. I thought Postgresql write and Ok, so when Postgresql doing a query for a second time for (very simple) example, FreeBSD can retrieve data from inactive mem too? Someone knows if there is a page which explains FreeBSD mechanisms about memory and fs cache management? I think I must read something on it :-) Thanks, -- Nicolas ...