On Mon, Jan 13, 2014 at 5:32 PM, Jim Nasby <j...@nasby.net> wrote: >> >> That's my point. In terms of kernel-postgres interaction, it's fairly >> simple. >> >> What's not so simple, is figuring out what policy to use. Remember, >> you cannot tell the kernel to put some page in its page cache without >> reading it or writing it. So, once you make the kernel forget a page, >> evicting it from shared buffers becomes quite expensive. > > > Well, if we were to collaborate with the kernel community on this then > presumably we can do better than that for eviction... even to the extent of > "here's some data from this range in this file. It's (clean|dirty). Put it > in your cache. Just trust me on this."
If I had a kernel developer hat, I'd put it on to say: I don't think allowing that last bit is wise for a kernel. It would violate oh-so-many separation rules and open an oh-so-big can-o-worms. -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
