On Thu, Apr 17, 2014 at 2:28 PM, Stephen Frost <sfr...@snowman.net> wrote: > > > On Thursday, April 17, 2014, Merlin Moncure <mmonc...@gmail.com> wrote: >> >> yeah -- the thing is, we are already too spendy already on >> supplemental write i/o (hint bits, visible bits, freezing, etc) and >> likely not worth it to throw something else on the pile unless the >> page is already dirty; the medium term trend in storage is that read >> vs write performance is becoming increasingly asymmetric, particularly >> on the random side so it's very unlikely to balance out. > > Guess I wasn't clear but I was thinking to read the page in, not do any > writing, and do it in a asynchronous way to the process doing the evicting.
no -- I got you. My point was, that's a pure guess unless you base it on evidence recorded on the page itself. Without that evidence, (which requires writing) the operating is in a a better place to make that guess so it's probably better to defer that decision. merlin -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
