On 05/15/2015 12:58 PM, Robert Haas wrote: > On Fri, May 15, 2015 at 3:35 PM, Josh Berkus <j...@agliodbs.com> wrote: >> On 05/15/2015 11:30 AM, Robert Haas wrote: >>> Once we enter beta (or even feature freeze), it's too late to whack >>> around the algorithm heavily. We're pretty much committed to >>> releasing and supporting whatever we have got at that point. I guess >>> we could revert it if it doesn't work out, but that's about the only >>> option at that point. We have more flexibility during the main part >>> of the development cycle. But your point is certainly valid and I >>> don't mean to dispute it. >> >> I will finally have a customer workload available to test this on this >> weekend. That's been rather delayed by the availability of customer >> hardware,because I'm not allowed to copy out the database. However, >> this is a database which suffers from multiple ndistinct estimation >> issues in production, so I should be able to get a set of stats back by >> Monday which would show how much of a general improvement it is. >> >> I realize that's after the deadline, but there wasn't much I could do >> about it. I've tried to simulate the kind of estimation issues I've >> seen, but they don't simulate well. > > This is clearly 9.6 material at this point, and has been for a while. > The patch - at least the last version I looked at - didn't store > anything different in pg_statistic. It just logged what it would have > stored. So testing is good, but there's not a question of pushing > this into 9.5.
I'm personally OK with that. The last thing we want to do is make query costing changes *in haste*. -- Josh Berkus PostgreSQL Experts Inc. http://pgexperts.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers