On Wed, Oct 9, 2013 at 02:34:19PM -0400, Robert Haas wrote: > On Wed, Oct 9, 2013 at 2:28 PM, Bruce Momjian <br...@momjian.us> wrote: > > On Wed, Oct 9, 2013 at 01:49:23PM -0400, Robert Haas wrote: > >> > Having really bad defaults so everyone knows they are bad really isn't > >> > user-friendly because the only people who know they are really bad are > >> > the people who are tuning them already. Again, we need to think of the > >> > typical user, not us. > >> > >> I think a typical user will be happier if we simply raise the default > >> rather than stick in an auto-tuning formula that's largely wishful > >> thinking. You're welcome to disagree, but you neither quoted nor > >> responded to my points about the sorts of scenarios in which that > >> might cause surprising and hard-to-debug results. > > > > Well, pointing out that is will be negative for some users (which I > > agree) doesn't refute that it will be better for most users. > > That is, of course, true. But I don't think you've made any argument > that the pros exceed the cons, or that the formula will in general be > accurate. It's massive simpler than what Josh says he uses, for > example, and he's not making the completely silly assumption that > available RAM is 4 * shared_buffers. An auto-tuning formula that's > completely inaccurate probably won't be better for most users.
I disagree. I think we can get a forumla that is certainly better than a fixed value. I think the examples I have shown do have better value than a default fixed value. I am open to whatever forumula people think is best, but I can't see how a fixed value is a win in general. -- Bruce Momjian <br...@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + Everyone has their own god. + -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
